Bug that allows ASF to shoot atlantis

**Describe the bug**
When using atlantis as air staging, enemy ASF (and maybe other air units) can "lock on" to the air units going into the atlantis. They then just shoot continuously and end up killing the atlantis unless it submerges

**To Reproduce**
#20811852
Took some time to reproduce. 7:15 is about when I get it to trigger. I believe it also triggers when air units are patrolling and go to the atlantis for repairs but I could not get that to work in the replay.

**Expected behavior**
Air units should not damage atlantis I guess

Thanks for your hard work guys!