Windows and possibly other things can fall down if the resin under them is destroyed

### Testmerges

N/A

### Round ID

N/A

### Description of the bug

These had resin walls under them and fell down after they were destroyed by marines.

### What's the difference with what should have happened?

Stuff that's not resin shoudn't be falling down when resin under them gets destroyed.

### How do we reproduce this bug?

1. Put some resin walls under something, probably needs to be on the edge.
2. Destroy that resin wall
3. See stuff fall down.
...

### Issue Bingo

- [x] Issue could be reproduced at least once
- [x] Issue happened in a recent (less than 7 days ago) round
- [x] Couldn't find an existing issue about this (https://github.com/cmss13-devs/cmss13/issues)

No source file, test, or entry point is named. Reproduce the issue by placing resin walls under another object and destroying a wall, then trace the resin-destruction and falling behavior. Done means non-resin objects remain supported when resin beneath them is removed, including the reported edge case.

Written by the indexing model from the issue text.