Adapts user mailer to event fetcher interface
Removes superfluous statement
Revert file deletion from previous commit
References correct user in test journal
Corrects project reference call
Merge remote-tracking branch 'opf/feature/squashed-migrations' into integration/normalize_acts_as_journalized
Removes all journals

Prevents checking data created by other tests

[skip ci]
Removes double key index
Adapts event fetcher interface
Respects existence of other generated data
Merge branch 'integration/normalize_acts_as_journalized' of github.com:opf/openproject into integration/normalize_acts_as_journalized