CircleCIでMySQLのイメージがビルドされない

現在Laravelでアプリケーションを作っています。そのアプリのテストを自動化しようとCircleCIを導入したのですが、その際にエラーにハマってしまったので質問させてください。

具体的にどのような問題が発生しているかというと、circleciの設定ファイルに書いた、MySQLのイメージがビルドされないというものです。MySQLのイメージをビルドしている際のLogは以下の通りです。

発生している問題・エラーメッセージ

テストを実行すると、MySQLのイメージのビルドがキャンセルされてしまいます。

2020-10-21 10:28:23+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.0.21-1debian10 started.
2020-10-21 10:28:23+00:00 [Note] [Entrypoint]: Initializing database files
2020-10-21T10:28:23.704088Z 0 [System] [MY-013169] [Server] /usr/sbin/mysqld (mysqld 8.0.21) initializing of server in progress as process 73
2020-10-21T10:28:23.705307Z 0 [Warning] [MY-013242] [Server] --character-set-server: 'utf8' is currently an alias for the character set UTF8MB3, but will be an alias for UTF8MB4 in a future release. Please consider using UTF8MB4 in order to be unambiguous.
2020-10-21T10:28:23.705319Z 0 [Warning] [MY-013244] [Server] --collation-server: 'utf8_unicode_ci' is a collation of the deprecated character set UTF8MB3. Please consider using UTF8MB4 with an appropriate collation instead.
2020-10-21T10:28:23.711279Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
2020-10-21T10:28:23.946407Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
2020-10-21T10:28:24.720528Z 6 [Warning] [MY-010453] [Server] root@localhost is created with an empty password ! Please consider switching off the --initialize-insecure option.
2020-10-21 10:28:26+00:00 [Note] [Entrypoint]: Database files initialized
2020-10-21 10:28:26+00:00 [Note] [Entrypoint]: Starting temporary server
mysqld will log errors to /var/lib/mysql/4b2586f26e24.err
mysqld is running as pid 178
2020-10-21 10:28:26+00:00 [Note] [Entrypoint]: Temporary server started.
Warning: Unable to load '/usr/share/zoneinfo/iso3166.tab' as time zone. Skipping it.
Warning: Unable to load '/usr/share/zoneinfo/leap-seconds.list' as time zone. Skipping it.
Warning: Unable to load '/usr/share/zoneinfo/zone.tab' as time zone. Skipping it.
Warning: Unable to load '/usr/share/zoneinfo/zone1970.tab' as time zone. Skipping it.
2020-10-21 10:28:28+00:00 [Note] [Entrypoint]: Creating database bookshelf
2020-10-21 10:28:28+00:00 [Note] [Entrypoint]: Creating user default
2020-10-21 10:28:28+00:00 [Note] [Entrypoint]: Giving user default access to schema bookshelf

2020-10-21 10:28:28+00:00 [Note] [Entrypoint]: Stopping temporary server
2020-10-21 10:28:30+00:00 [Note] [Entrypoint]: Temporary server stopped

2020-10-21 10:28:30+00:00 [Note] [Entrypoint]: MySQL init process done. Ready for start up.

2020-10-21T10:28:30.517867Z 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.21) starting as process 8
2020-10-21T10:28:30.520304Z 0 [Warning] [MY-013242] [Server] --character-set-server: 'utf8' is currently an alias for the character set UTF8MB3, but will be an alias for UTF8MB4 in a future release. Please consider using UTF8MB4 in order to be unambiguous.
2020-10-21T10:28:30.520320Z 0 [Warning] [MY-013244] [Server] --collation-server: 'utf8_unicode_ci' is a collation of the deprecated character set UTF8MB3. Please consider using UTF8MB4 with an appropriate collation instead.
2020-10-21T10:28:30.526812Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
2020-10-21T10:28:30.672751Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
2020-10-21T10:28:30.750389Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Bind-address: '::' port: 33060, socket: /var/run/mysqld/mysqlx.sock
2020-10-21T10:28:30.843018Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed.
2020-10-21T10:28:30.843186Z 0 [System] [MY-013602] [Server] Channel mysql_main configured to support TLS. Encrypted connections are now supported for this channel.
2020-10-21T10:28:30.844994Z 0 [Warning] [MY-011810] [Server] Insecure configuration for --pid-file: Location '/var/run/mysqld' in the path is accessible to all OS users. Consider choosing a different directory.
2020-10-21T10:28:30.860565Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.21'  socket: '/var/run/mysqld/mysqld.sock'  port: 3306  MySQL Community Server - GPL.


Build was canceled

該当のソースコード

CircleCIの設定ファイルは以下の通りです。

version: 2
jobs:
  build:
    docker:
      # Specify the version you desire here
      - image: circleci/php:7.3-node-browsers
      - image: circleci/mysql:8.0.21
        environment:
          MYSQL_DATABASE: bookshelf
          MYSQL_USER: default
          MYSQL_PASSWORD: secret

    environment:
      APP_ENV: testing
      DB_CONNECTION: mysql
      DB_HOST: mysql
      DB_PORT: 3306
      DB_DATABASE: bookshelf
      DB_USERNAME: default
      DB_PASSWORD: secret

    steps:
      - checkout
      - restore_cache:
          key: composer-v1-{{ checksum "composer.lock" }}
      - run: composer install -n --prefer-dist
      - save_cache:
          key: composer-v1-{{ checksum "composer.lock" }}
          paths:
            - vendor
      - restore_cache:
          key: npm-v1-{{ checksum "package-lock.json" }}
      - run:
          name: npm ci
          command: |
            if [ ! -d node_modules ]; then
              npm ci
            fi
      - save_cache:
          key: npm-v1-{{ checksum "package-lock.json" }}
          paths:
            - node_modules
      - run: npm run dev
      - run:
          name: get ready for mysql
          command: |
            sudo apt-get update
            sudo docker-php-ext-install pdo_mysql
            dockerize -wait tcp://localhost:3306 -timeout 2m
      - run:
          name: php test
          command: vendor/bin/phpunit