ci: Pin old Bundler for Ruby 2.7 and release others

This inverts the dependency strategy and within the CI matrix allows everything
to use the latest except for Ruby 2.7 which is known to fail with later Bundler
versions.

Author: tokengeek

.github/workflows/ruby.yml

@@ -22,19 +22,20 @@ jobs:
       fail-fast: false
       matrix:
         ruby: ["2.7", "3.0", "3.1", "3.2", "3.3", "head"]
+        include:
+          - ruby: "2.7"
+            bundler: "2.4.22"
     env:
       DEBUG: "true"
     steps:
     - uses: actions/checkout@v3
-    - name: Remove bundler version pin for head Ruby
-      if: matrix.ruby == 'head'
-      run: sed -i '/^BUNDLED WITH/{N;d}' Gemfile.lock
     - name: Set up Ruby ${{ matrix.ruby }}
     # To automatically get bug fixes and new Ruby versions for ruby/setup-ruby,
     # change this to (see https://github.com/ruby/setup-ruby#versioning):
       uses: ruby/setup-ruby@v1
       with:
         ruby-version: ${{ matrix.ruby }}
+        bundler: ${{ matrix.bundler || 'default' }}
         bundler-cache: true
     - name: Run tests
       run: bundle exec rake

Gemfile.lock

@@ -132,6 +132,3 @@ DEPENDENCIES
   simplecov
   vcr (~> 2.5)
   webmock
-
-BUNDLED WITH
-   2.4.22