Xenomorphs and other creatures can vent crawl into scrubbers, but those can't be welded.

[lbnesquik]

Brief description of the bug

Xenomorphs can crawl into vents and scrubbers, but you are only able to weld vents at the moment. Given there is always a scrubber around vents, this is a little problematic.

What you expected to happen

Be able to weld all entry/exit points to the vent system.

What actually happened

You hit the scrubber and nothing happen.

Steps to reproduce

• Get welder
• Try to weld vent. It works.
• Try to weld scrubber, it doesn't.
• Get pounced.