If a Rails 6 Gemfile includes ruby "~> 3.0" and the current Ruby version in the project is 3.0.1, how does one upgrade Ruby to the highest current minor release (3.0.2 at this time) without modifying the Gemfile to specify an exact minor release (which would defeat the purpose of the "~> 3.0")?
The specifier ~> has a special meaning, best shown by example. ~> 3.0 is identical to >= 3.0 and < 3.1. So all minor patches are included. See https://bundler.io/gemfile.html.
No need to change your Gemfile just install the gems in the newly installed Ruby version.