Pass rubygems_api_key secret to release workflow

The reusable release workflow requires the RUBYGEMS_API_KEY secret
to publish gems to RubyGems.

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: tvdeyen

.github/workflows/release.yml

@@ -16,3 +16,4 @@ jobs:
     secrets:
       app_id: ${{ vars.ALCHEMY_BOT_APP_ID }}
       app_private_key: ${{ secrets.ALCHEMY_BOT_APP_PRIVATE_KEY }}
+      rubygems_api_key: ${{ secrets.RUBYGEMS_API_KEY }}