ci: add AI Moderator workflow for issue and comment detection

[UlisesGascon]

Hey @erwinmombay and @RafaelGSS. Here is a proposal to start solving the AI generated comments, issues, PRs, etc..

I created an small feedback issue to the GitHub team asking for additional features github/ai-moderator#22, but in the meantime this is what we can achieve:

• ✅ Hide spam comments on PRs and issues
• ✅ Include the tag ai-generated when a new comment has been moderated in a issue.
• ✅ The execution time is fast (unless for the first execution) like few seconds and there is no need for additional GH PAT tokens
• ❌ Moderate PR description
• ❌ Moderate Issue description
• ❌ Auto-close or lock issues and PRs

Demo

• 🚨 Official ETH Giveaway — 10,000 ETH to the community! UlisesGascon/amphtml#3
• ✨ PV-18487 support refererpolicy with amp-dailymotion UlisesGascon/amphtml#2

Additional things:

We can add a separate workflow that can close issues tagged as ai-generated but that will close any issue where a random AI comment is added, so probably is not something that we want

[CLAassistant]

All committers have signed the CLA.