Update CI workflow to use x86_64-linux-gnu platform

Nokogiri 1.18.10+ uses x86_64-linux-gnu instead of x86_64-linux as
the platform identifier. Updated the CI workflow to use the correct
platform and removed the arm64-darwin-24 platform from Gemfile.lock
to keep it consistent with CI expectations.

This fixes the check_react_and_ujs test failures where Gemfile.lock
was being modified during CI runs.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: justin808

.github/workflows/ruby.yml

@@ -47,7 +47,7 @@ jobs:
           path: vendor/bundle
           key: root-gem-cache-${{ hashFiles('Gemfile.lock') }}
       - name: Install Ruby Gems
-        run: bundle lock --add-platform 'x86_64-linux' && bundle check --path=vendor/bundle || bundle _2.4.9_ install --path=vendor/bundle --jobs=4 --retry=3
+        run: bundle lock --add-platform 'x86_64-linux-gnu' && bundle check --path=vendor/bundle || bundle _2.4.9_ install --path=vendor/bundle --jobs=4 --retry=3
       - run: yarn
       - run: bundle exec rake react:update
       - run: bundle exec rake ujs:update
@@ -114,7 +114,7 @@ jobs:
         path: test/dummy/vendor/bundle
         key: dummy-app-gem-cache-${{ hashFiles(format('{0}/gemfiles/{1}.gemfile.lock', github.workspace, matrix.gemfile)) }}
     - name: Install Ruby Gems for dummy app
-      run: bundle lock --add-platform 'x86_64-linux' && bundle check --path=test/dummy/vendor/bundle || bundle _2.4.9_ install --frozen --path=test/dummy/vendor/bundle --jobs=4 --retry=3
+      run: bundle lock --add-platform 'x86_64-linux-gnu' && bundle check --path=test/dummy/vendor/bundle || bundle _2.4.9_ install --frozen --path=test/dummy/vendor/bundle --jobs=4 --retry=3
     - run: cd test/dummy && yalc add react_ujs && ${{ matrix.js_package_manager.installer }} install
     - run: bundle exec rake test
       env:

Gemfile.lock

@@ -171,8 +171,6 @@ GEM
     net-smtp (0.5.0)
       net-protocol
     nio4r (2.7.3)
-    nokogiri (1.18.10-arm64-darwin)
-      racc (~> 1.4)
     nokogiri (1.18.10-x86_64-darwin)
       racc (~> 1.4)
     nokogiri (1.18.10-x86_64-linux-gnu)
@@ -254,7 +252,6 @@ GEM
     zeitwerk (2.6.6)
 
 PLATFORMS
-  arm64-darwin-24
   x86_64-darwin-20
   x86_64-linux
   x86_64-linux-gnu