Bump ruby/setup-ruby from 1.305.0 to 1.312.0

Bumps [ruby/setup-ruby](https://github.com/ruby/setup-ruby) from 1.305.0 to 1.312.0.
- [Release notes](https://github.com/ruby/setup-ruby/releases)
- [Changelog](https://github.com/ruby/setup-ruby/blob/master/release.rb)
- [Commits](https://github.com/ruby/setup-ruby/compare/0cb964fd540e0a24c900370abf38a33466142735...12fd324f1d0b43274fdc8130f6980590a667c455)

---
updated-dependencies:
- dependency-name: ruby/setup-ruby
  dependency-version: 1.312.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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