Automatically quickmatch new authors

[MxMarx]

Automatically do a quick match when new authors are found by the scanner.
It might be better if this was a toggleable option instead, but I'm still super new at this and wasn't sure if this was the best approach.

Somewhat related to #1789, #1490

[advplyr]

I think this should be handled as a background task after the scan is complete. Mainly because if you are scanning in a new library it may be creating many new authors and come up against the rate limit #1570

If we implement the rate limiter in #2188 it would slow down the scanner. The TaskManager was started to allow for notifying the client of background tasks. I was thinking of implementing an auto quick match of books setting that would run after the scan for new books.