Fix gems.rb lockfile for bundler version lookup in template

[TonyCTHsu]

What was the end-user or developer problem that led to this PR?

When I create a rails 7 project with rails new my_app --minimal , there are a couple of files under bin provided from bundler. bin/bundle caught my attention with

  def lockfile
    lockfile =
      case File.basename(gemfile)
      when "gems.rb" then gemfile.sub(/\.rb$/, gemfile)
      else "#{gemfile}.lock"
      end
    File.expand_path(lockfile)
  end

This line: when "gems.rb" then gemfile.sub(/\.rb$/, gemfile)

When provided with gems.rb, the lockfile ends up become gemsgems.rb, which is very likely that the file is missing and this expression is returning false and prevent reading bundler version from the lockfile.

I noticed that the filename(Gemfile/gems.rb, Gemfile.lock/gems.locked) is probably not that important, since the content is the same, but Bundler has a specific mapping for gems.rb to gems.locked I think should be respected.

What is your fix for the problem, implemented in this PR?

The fix changes the lockfile lookup for gems.rb during bundler version lookup. Respect the bundler version specified in gems.locked.

Make sure the following tasks are checked

• Describe the problem / feature
• Write tests for features and bug fixes
• Write code to solve the problem
• Make sure you follow the current code style and write meaningful commit messages without tags

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[deivid-rodriguez]

Looks great, nice catch!

Do you mind rebasing and squashing the commits into one. I like to have the fix and the test to illustrate/exercise it in the same commit.