allows the SC/FISHER to shoot floor lights (#83182)

## About The Pull Request
Lowers the hit threshold layer of SC/FISHER bolts from
`PROJECTILE_HIT_THRESHHOLD_LAYER` (2.75) to `LOW_OBJ_LAYER` (2.5),
allowing you to shoot floor lights with it.

## Why It's Good For The Game
floor lights count as lightbulbs and therefore you should be able to
explode them with the gun that explodes lightbulbs

## Changelog

:cl:
fix: The SC/FISHER can now shoot floor lights.
/:cl:

Co-authored-by: Hatterhat <Hatterhat@users.noreply.github.com>

code/modules/projectiles/projectile/special/saboteur.dm

@@ -7,6 +7,7 @@
 	range = 21
 	projectile_phasing = PASSTABLE | PASSMOB | PASSMACHINE | PASSSTRUCTURE
 	hitscan = TRUE
+	hit_threshhold = LOW_OBJ_LAYER // required to be able to hit floor lights
 	var/disrupt_duration = 15 SECONDS
 
 /obj/projectile/energy/fisher/on_hit(atom/target, blocked, pierce_hit)