Nobody seems to care that there is no fire supression equipment in that hangar
What's this got to do with anything. Does fire suppression equipment improve maintenance quality or something???
Anyway on most major airports the level of fire suppression equipment is usually a product of hangar size (volume). The big requirements tend to kick in at 20,000 cubic metres. I doubt Skytrans plastic shed would be even 10,000, so hose reels and extinguishers would be probably all they need.
Some pics in here of their hangar:
Aviation Industry - Global Fabric Structures
Looks like a hose reel in a least one of the pictures. So it appears they do have fire suppression.