gogs.service: Remove syslog.target (#7681)

Remove syslog.target from service file, this target hasn't existed for
over a decade.


https://github.com/systemd/systemd/blob/6aa8d43ade72e24c9426e604f7fc4b7582b9db7c/NEWS#L72-L73

scripts/systemd/gogs.service

@@ -1,6 +1,5 @@
 [Unit]
 Description=Gogs
-After=syslog.target
 After=network.target
 After=mariadb.service mysql.service mysqld.service postgresql.service memcached.service redis.service