Prevent creation of instance methods when `instance_reader = false`, Grammar checks, Conditional statements combined
Merge pull request #13401 from akshay-vishnoi/refactor

Prevent creation of instance methods when `instance_reader = false`, Grammar checks, Conditional statements combined
[ci skip] Remove <tt> tag in 4_1_release notes.
Merge pull request #13404 from JuanitoFatas/remove-tt

[ci skip] Remove <tt> tag in 4_1_release notes.
Fix assertions for testing unknown formats using Mime::NullType
Fixed configurable.rb regular expression name check
Merge pull request #13406 from hincupetru/master

Fixed configurable.rb regular expression name check