Make webfinger find actors for queries on actor URIs and URLs.

[SaulMoonves]

Description

Make webfinger queries on actor URIs and URLs (which are returned as aliases on typical actor webfinger responses) return the corresponding actor. This matches existing functionality on Mastodon and Pleroma and Misskey.

This should not change behavior of any existing queries or behavior, (tests were ran to make sure) just adds additional valid behavior for certain types of queries. However if a URL is passed that does not match a URI or URL regex, a new, distinct error message will be returned. But I didn't find any tests relying on this behavior.

The changes were tested against the local test harness server, but not a live server just FYI.

closes #1415

Checklist

Please put an x inside each checkbox to indicate that you've read and followed it: [ ] -> [x]

If this is a documentation change, only the first checkbox must be filled (you can delete the others if you want).

• I/we have read the GoToSocial contribution guidelines.
• I/we have discussed the proposed changes already, either in an issue on the repository, or in the Matrix chat.
• I/we have performed a self-review of added code.
• I/we have written code that is legible and maintainable by others.
• I/we have commented the added code, particularly in hard-to-understand areas.
• I/we have made any necessary changes to documentation.
• I/we have added tests that cover new code.
• I/we have run tests and they pass locally with the changes.
• I/we have run go fmt ./... and golangci-lint run.

I go fmt'ed my changes, but after some effort I failed to figure out how to do "golangci-lint run", I'm sorry.

[SaulMoonves]

Okay, it looks like your automated stuff did linting I couldn't figure out and found problems, i have fixed them and everything seems happy now.

[NyaaaWhatsUpDoc]

We are not interested in taking contributions or working with somone happy to remain civil with transphobes (Alex Gleason). You posted knowing about the lack of support between soapbox and gotosocial so this is something you were at least marginally aware of.