[3.34] scrobbler: Fix lastfm account removal
When, a GOA account is removed, the credentials and the account parameters are not reset. Thus, LastFmScrobbler will still try to scrobble even if the account does not exist anymore. This results in a crash.
Fix the issue by resetting all GoaLastFM parameters when a Last.fm account is removed.
Closes: #145 (closed) (cherry picked from commit d368111c)