Heroku デプロイ

Herokuを使ってデプロイしようとしたところ以下のエラーが出ました
初めて使うのでよくわかりません何が原因なのでしょうか　ご教授願います
下記のサイトを参考にしました
https://qiita.com/kazukimatsumoto/items/a0daa7281a3948701c39

ターミナルで$heroku login を実行した場合ターミナルでeメールとパスワードの入力を求められるみたいですが自分は以下のページに遷移します
$heroku -vをするとバージョン情報が表示されるのでインストールは成功してると思います

Enumerating objects: 894, done.
Counting objects: 100% (894/894), done.
Delta compression using up to 4 threads
Compressing objects: 100% (845/845), done.
Writing objects: 100% (894/894), 128.23 KiB | 2.85 MiB/s, done.
Total 894 (delta 520), reused 0 (delta 0)
remote: Compressing source files... done.
remote: Building source:
remote: 
remote:  !     error fetching custom buildpack https://git.heroku.com/whispering-ridge-73721.git
remote: 
remote:  !     Push failed
remote: Verifying deploy...
remote: 
remote: !	Push rejected to whispering-ridge-73721.
remote: 
To https://git.heroku.com/whispering-ridge-73721.git
 ! [remote rejected] master -> master (pre-receive hook declined)
error: failed to push some refs to 'https://git.heroku.com/whispering-ridge-73721.git'

Gemfile

source 'https://rubygems.org'

git_source(:github) do |repo_name|
  repo_name = "#{repo_name}/#{repo_name}" unless repo_name.include?("/")
  "https://github.com/#{repo_name}.git"
end


# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '~> 5.0.7', '>= 5.0.7.2'
# Use mysql as the database for Active Record
# gem 'mysql2', '>= 0.3.18', '< 0.6.0'
# Use Puma as the app server
gem 'puma', '~> 3.0'
# Use SCSS for stylesheets
gem 'sass-rails', '~> 5.0'
# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'
# Use CoffeeScript for .coffee assets and views
gem 'coffee-rails', '~> 4.2'
# See https://github.com/rails/execjs#readme for more supported runtimes
# gem 'therubyracer', platforms: :ruby

# Use jquery as the JavaScript library
gem 'jquery-rails'
# Turbolinks makes navigating your web application faster. Read more: https://github.com/turbolinks/turbolinks
gem 'turbolinks', '~> 5'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 2.5'
# Use Redis adapter to run Action Cable in production
# gem 'redis', '~> 3.0'
# Use ActiveModel has_secure_password
# gem 'bcrypt', '~> 3.1.7'

# Use Capistrano for deployment
# gem 'capistrano-rails', group: :development

group :development, :test do
  # Call 'byebug' anywhere in the code to stop execution and get a debugger console
  gem 'byebug', platform: :mri
  gem 'pry-rails'
end

group :development do
  # Access an IRB console on exception pages or by using <%= console %> anywhere in the code.
  gem 'web-console', '>= 3.3.0'
  gem 'listen', '~> 3.0.5'
  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
  gem 'spring'
  gem 'spring-watcher-listen', '~> 2.0.0'
end
gem 'carrierwave'
gem 'fog-aws'

# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]
gem 'haml-rails'
gem "font-awesome-rails"
gem 'devise'
gem 'carrierwave'
gem 'mini_magick'
gem 'rspec-rails', '~> 3.5'
gem 'rails-controller-testing'
gem 'factory_bot_rails'
gem 'faker'
group :test, :development do 
  gem 'capybara'
end
# group :production do
#   gem 'unicorn', '5.4.1'
# end
# group :development, :test do
#   gem 'capistrano'
#   gem 'capistrano-rbenv'
#   gem 'capistrano-bundler'
#   gem 'capistrano-rails'
#   gem 'capistrano3-unicorn'
# end

group :production do
  gem 'pg'
end

group :development, :test do
  gem 'mysql2' 
end

database.yml

# MySQL. Versions 5.0 and up are supported.
#
# Install the MySQL driver
#   gem install mysql2
#
# Ensure the MySQL gem is defined in your Gemfile
#   gem 'mysql2'
#
# And be sure to use new-style password hashing:
#   http://dev.mysql.com/doc/refman/5.7/en/old-client.html
#
default: &default
  adapter: mysql2
  encoding: utf8
  pool: 5
  username: root
  password:
  socket: /tmp/mysql.sock

development:
  <<: *default
  database: MyApri_development

# Warning: The database defined as "test" will be erased and
# re-generated from your development database when you run "rake".
# Do not set this db to the same as development or production.
test:
  <<: *default
  database: MyApri_test

# As with config/secrets.yml, you never want to store sensitive information,
# like your database password, in your source code. If your source code is
# ever seen by anyone, they now have access to your database.
#
# Instead, provide the password as a unix environment variable when you boot
# the app. Read http://guides.rubyonrails.org/configuring.html#configuring-a-database
# for a full rundown on how to provide these environment variables in a
# production deployment.
#
# On Heroku and other platform providers, you may have a full connection URL
# available as an environment variable. For example:
#
#   DATABASE_URL="mysql2://myuser:mypass@localhost/somedatabase"
#
# You can use this database configuration with:
#
#   production:
#     url: <%= ENV['DATABASE_URL'] %>
#
production:
  <<: *default
  database: MyApri_production
  username: MyApri
  password: <%= ENV['MYAPRI_DATABASE_PASSWORD'] %>
  adapter: postgresql
  encoding: unicode
  pool: 5