HTTP git clones will show 401/200s in the logs

What does this MR do?

Adds some documentation on the behaviour seen in the logs when you clone via HTTP.

Seeing 401 entries in the logs are normally a red flag, but in this case they are expected.

Inspired from the following sources - I tried as much as possible not to copy/paste 😄

• https://confluence.atlassian.com/bitbucketserverkb/two-401-responses-for-every-git-operation-938854756.html
• https://github.com/go-gitea/gitea/issues/7412

Update: I've also added a related 403 section that talks about how to identify if your IP address has been blocked by Rack Attack.

Related issues

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