Remove reference to Glitch from GitHub App Manifest Page #43934

Code of Conduct

• I have read and agree to the GitHub Docs project's Code of Conduct

What article on docs.github.com is affected?

https://docs.github.com/en/apps/sharing-github-apps/registering-a-github-app-from-a-manifest#hosting-your-app-with-glitch

What part(s) of the article would you like to see updated?

The page detailing how to register a GitHub App from a manifest references hosting a Probot app from Glitch, which is (very sadly 😞) defunct. Let's remove it so it's accurate.

Additional information

No response