v4.2.0

Features

• Add support for optional: false in belongs_to associations. (#1237)
• Add support for associations with inverse_of: false and non-standard foreign key (#1106)

Bug fixes

• Fix typos in documentation of allow_values (#1241)
• Fix appraisal command in CONTRIBUTING.md file (#1253)

Improvements

• Remove minitest-reporters dependency ([#1251])
• Development dependency updates