我正在将 Heroku 与 Rails 6 和 Postgres 一起使用。我试图用来heroku open启动应用程序，但构建失败，这显示在日志中：
-----> Detecting rake tasks
-----> Preparing app for Rails asset pipeline
Running: rake assets:precompile
DEPRECATION WARNING: Including LoggerSilence is deprecated and will be removed in Rails 6.1. Please use `ActiveSupport::LoggerSilence` instead (called from <top (required)> at /tmp/build_9537ba0878cb8933c15686548eb3ccb5/config/application.rb:7)
Missing encryption key to decrypt file with. Ask your team for your master key and write it to /tmp/build_9537ba0878cb8933c15686548eb3ccb5/config/master.key or put it in the ENV['RAILS_MASTER_KEY'].
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! Precompiling assets failed.
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