Tweak: Improved database performance for new installations

For now, we don’t want to start DB migration for current plugin installations.

If we see this patch will help, we will consider migration.

So, if you want right now to get this, you need to disable the plugin, drop the table, and activate it again.

If you know how to add indexes to your current table, you can compare it by this scheme: https://github.com/pojome/activity-log/blob/master/classes/class-aal-maintenance.php#L60-L80

Thanks