sync-shared-config: fix style and style checks.

- Use `exclude?` instead of `include?` to make RuboCop happy
- Properly check the `sync` jobs success so that auto-merge is not
  run if jobs are failing

.github/actions/sync/shared-config.rb

@@ -175,7 +175,7 @@ def git(*args)
 end
 
 # Update Gemfile.lock if it exists, based on the Ruby version.
-if !custom_ruby_version_repos.include?(repository_name) && (target_directory_path/"Gemfile.lock").exist?
+if custom_ruby_version_repos.exclude?(repository_name) && (target_directory_path/"Gemfile.lock").exist?
   Dir.chdir target_directory_path do
     puts "Running bundle install..."
     system "bundle update --ruby --bundler --quiet >/dev/null"

.github/workflows/sync-shared-config.yml

@@ -115,6 +115,7 @@ jobs:
   conclusion:
     needs: sync
     runs-on: ubuntu-latest
+    if: always()
     steps:
-      - name: Conclusion
-        run: echo "Sync shared configurations completed"
+      - name: Result
+        run: ${{ needs.sync.result == 'success' }}