Attempt to re-root to surface-attached part results in infinite loop.

[whale2]

Steps to reproduce:
Add proc tank
Attach any other part to it by surface-attaching it.
Re-root the vessel with surface-attached part being new root.

https://i.imgur.com/wTKh4oV.png

I'm pretty sure the code goes into infinite loop here:
https://github.com/Tidal-Stream/ProceduralParts/blob/master/Source/ProceduralPart.cs#L1380

but I don't have enough experience with KSP editor internals.

[astro-stan]

+1. See the attached issue.