This is a proposal to address the following issues:

• Lint/UselessMethodDefinition has a conflict with Rails/LexicallyScopedActionFilter when used with Rails before_action rubocop#8667
• Cop Rails/LexicallyScopedActionFilter conflicts with Lint/UselessMethodDefinition #343

Currently, Rails/LexicallyScopedActionFilter is enabled by default for controllers and mailers.

Given this, I thought it would be reasonable to disable Lint/UselessMethodDefinition by default for them as well.

Before submitting the PR make sure the following are checked:

• The PR relates to only one subject with a clear title and description in grammatically correct, complete sentences.
• Wrote good commit messages.
• Commit message starts with [Fix #issue-number] (if the related issue exists).
• Feature branch is up-to-date with master (if not - rebase it).
• Squashed related commits together.
• Added tests.
• Ran bundle exec rake default. It executes all tests and runs RuboCop on its own code.
• Added an entry (file) to the changelog folder named {change_type}_{change_description}.md if the new code introduces user-observable changes. See changelog entry format for details.
• If this is a new cop, consider making a corresponding update to the Rails Style Guide.