Merge pull request #105 from ruby/pin-rg-3-3-ruby-2-5

Pin RubyGems 3.3 for Ruby 2.5

Author: hsbt

.github/workflows/test.yml

@@ -32,9 +32,14 @@ jobs:
         with:
           ruby-version: ${{ matrix.ruby }}
           bundler-cache: true # 'bundle install' and cache
-      - name: Ensure new-enough RubyGems
+      - name: Ensure new-enough RubyGems for Ruby 2.6
         run: gem update --system
-        if: ${{ matrix.ruby == '2.6' || matrix.ruby == '2.5' }}
+        if: ${{ matrix.ruby == '2.6' }}
+      - name: Ensure new-enough RubyGems for Ruby 2.5
+        run: |
+          gem install rubygems-update -v "~> 3.3.26"
+          update_rubygems
+        if: ${{ matrix.ruby == '2.5' }}
       - name: Run test
         run: bundle exec rake
         env: