現在、ポートフォリオ作成中の初学者です。
ポートフォリオにdockerを導入しようとしていたところエラー発生し、調べても手がかりなる記事がなかったためご教授いただきたです。

環境

ruby 2.6.5
rails 6.0.3
mysql 8.0.23
#状況
既存のrailsアプリにdockerを導入するに当たって以下の記事を参考に行いました。
既存のRailsアプリのローカル環境にDockerを導入する方法【Rails6 / MySQL8】
まずDockerfileとdocker-compose.ymlを以下のように記述しました
Dockerfile

FROM ruby:2.6.5
RUN curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add - \
    && echo "deb https://dl.yarnpkg.com/debian/ stable main" | tee /etc/apt/sources.list.d/yarn.list
RUN apt-get update -qq && apt-get install -y build-essential libpq-dev nodejs yarn
WORKDIR /sdf-app
COPY Gemfile ./Gemfile
COPY Gemfile.lock ./Gemfile.lock
RUN gem install bundler
RUN bundle install
COPY . /sdf-app
COPY entrypoint.sh /usr/bin/
RUN chmod +x /usr/bin/entrypoint.sh
ENTRYPOINT ["entrypoint.sh"]
EXPOSE 3000
CMD ["rails", "server", "-b", "0.0.0.0"]

docker-compose.yml

version: '3' #docker-composeのバージョン
services:
  db:
    image: mysql:8.0.23 #既存アプリとあわせる。ターミナルに[$ mysql --version]で確認
    environment:
      MYSQL_ROOT_PASSWORD: (database.ymlのdefaultのpassword:を記述)
      MYSQL_DATABASE: root
    ports:
      - "4306:3306"
    volumes:
      - ./mysql-confd:/etc/mysql/conf.d
  web:
    build: .
    command: bash -c "rm -f tmp/pids/server.pid && bundle exec rails s -p 3000 -b '0.0.0.0'"
    volumes:
      - .:/sdf-app
    ports:
      - 3000:3000
    depends_on:
      - db
    tty: true
    stdin_open: true
volumes:
  mysql-data:

記述後

docker-compose build

docker-compose up -d

に成功し

sdf-app % docker-compose run web rails db:create

実行時に以下のエラーが発生しました
#エラーログ

sdf-app % docker-compose run web rails db:create
Creating sdf-app_web_run ... done
warning: parser/current is loading parser/ruby26, which recognizes
warning: 2.6.6-compliant syntax, but you are running 2.6.5.
warning: please see https://github.com/whitequark/parser#compatibility-with-ruby-mri.
Plugin caching_sha2_password could not be loaded: /usr/lib/x86_64-linux-gnu/mariadb19/plugin/caching_sha2_password.so: cannot open shared object file: No such file or directory
Couldn't create 'sample_app_development' database. Please check your configuration.
rails aborted!
Mysql2::Error::ConnectionError: Plugin caching_sha2_password could not be loaded: /usr/lib/x86_64-linux-gnu/mariadb19/plugin/caching_sha2_password.so: cannot open shared object file: No such file or directory
/usr/local/bundle/gems/mysql2-0.5.3/lib/mysql2/client.rb:90:in `connect'
/usr/local/bundle/gems/mysql2-0.5.3/lib/mysql2/client.rb:90:in `initialize'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/connection_adapters/mysql2_adapter.rb:24:in `new'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/connection_adapters/mysql2_adapter.rb:24:in `mysql2_connection'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/connection_adapters/abstract/connection_pool.rb:887:in `new_connection'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/connection_adapters/abstract/connection_pool.rb:931:in `checkout_new_connection'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/connection_adapters/abstract/connection_pool.rb:910:in `try_to_checkout_new_connection'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/connection_adapters/abstract/connection_pool.rb:871:in `acquire_connection'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/connection_adapters/abstract/connection_pool.rb:593:in `checkout'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/connection_adapters/abstract/connection_pool.rb:437:in `connection'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/connection_adapters/abstract/connection_pool.rb:1119:in `retrieve_connection'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/connection_handling.rb:221:in `retrieve_connection'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/connection_handling.rb:189:in `connection'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/tasks/mysql_database_tasks.rb:8:in `connection'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/tasks/mysql_database_tasks.rb:16:in `create'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/tasks/database_tasks.rb:126:in `create'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/tasks/database_tasks.rb:185:in `block in create_current'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/tasks/database_tasks.rb:479:in `block (2 levels) in each_current_configuration'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/tasks/database_tasks.rb:476:in `each'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/tasks/database_tasks.rb:476:in `block in each_current_configuration'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/tasks/database_tasks.rb:475:in `each'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/tasks/database_tasks.rb:475:in `each_current_configuration'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/tasks/database_tasks.rb:184:in `create_current'
/usr/local/bundle/gems/activerecord-6.0.3.5/lib/active_record/railties/databases.rake:39:in `block (2 levels) in <main>'
/usr/local/bundle/gems/railties-6.0.3.5/lib/rails/commands/rake/rake_command.rb:23:in `block in perform'
/usr/local/bundle/gems/railties-6.0.3.5/lib/rails/commands/rake/rake_command.rb:20:in `perform'
/usr/local/bundle/gems/railties-6.0.3.5/lib/rails/command.rb:48:in `invoke'
/usr/local/bundle/gems/railties-6.0.3.5/lib/rails/commands.rb:18:in `<main>'
/usr/local/bundle/gems/bootsnap-1.7.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:23:in `require'
/usr/local/bundle/gems/bootsnap-1.7.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:23:in `block in require_with_bootsnap_lfi'
/usr/local/bundle/gems/bootsnap-1.7.3/lib/bootsnap/load_path_cache/loaded_features_index.rb:92:in `register'
/usr/local/bundle/gems/bootsnap-1.7.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:22:in `require_with_bootsnap_lfi'
/usr/local/bundle/gems/bootsnap-1.7.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:31:in `require'
/sdf-app/bin/rails:9:in `<top (required)>'
/usr/local/bundle/gems/spring-2.1.1/lib/spring/client/rails.rb:28:in `load'
/usr/local/bundle/gems/spring-2.1.1/lib/spring/client/rails.rb:28:in `call'
/usr/local/bundle/gems/spring-2.1.1/lib/spring/client/command.rb:7:in `call'
/usr/local/bundle/gems/spring-2.1.1/lib/spring/client.rb:30:in `run'
/usr/local/bundle/gems/spring-2.1.1/bin/spring:49:in `<top (required)>'
/usr/local/bundle/gems/spring-2.1.1/lib/spring/binstub.rb:11:in `load'
/usr/local/bundle/gems/spring-2.1.1/lib/spring/binstub.rb:11:in `<top (required)>'
/sdf-app/bin/spring:15:in `<top (required)>'
bin/rails:3:in `load'
bin/rails:3:in `<main>'
Tasks: TOP => db:create
(See full trace by running task with --trace)
ERROR: 1

#調べたこと
mysqlのバージョンが8系だとプラグインをインストールする必要があるらしいそれがインストールされていないと

Mysql2::Error::ConnectionError: Plugin caching_sha2_password could not be loaded: /usr/lib/x86_64-linux-gnu/mariadb19/plugin/caching_sha2_password.so: cannot open shared object file: No such file or directory
/usr/local/bundle/gems/mysql2-0.5.3/lib/mysql2/client.rb:90:in `connect'

上記のエラーが起きると分かったのですが、そのプラグインをインストールするコードがわからずにいる状態ですので、わかる方ご教授お願いします。