Ruby 3.4 will promote bigdecimal gem to a bundled gem in order to improve maintenancebility. To migrate to Ruby 3.4 easily, Ruby 3.3 warns a use of bigdecimal if it's not added to dependencies.
/build/lib/mysql2.rb:2: warning: bigdecimal was loaded from the standard library, but will no longer be part of the default gems since Ruby 3.4.0. Add bigdecimal to your Gemfile or gemspec.
Ruby 3.4 will promote bigdecimal gem to a bundled gem in order to improve maintenancebility. To migrate to Ruby 3.4 easily, Ruby 3.3 warns a use of bigdecimal if it's not added to dependencies.
https://github.com/brianmario/mysql2/actions/runs/8972155446/job/24639503831#step:4:238
So this patch adds bigdecimal to runtime dependencies.
I know bigdecimal is not always necessary, but I'd like to prevent a lot of users from adding the gem to their Gemfile manually.
Ref. https://bugs.ruby-lang.org/issues/20187 Slides from RubyKaigi 2024: https://speakerdeck.com/andpad/long-journey-of-ruby-standard-library-rubykaigi-2024