Fix set_body_cover_flags() (#7145)

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## About The Pull Request
As a programmer your code is like your children, hit them to make them
work harder.

Fixes /obj/item/proc/set_body_cover_flags() to actually set body cover
flags.
This should fix:
-Being unable to eat with your mask down
-Masks working for breathing when down
-Raised glasses like welding helmets giving you protection when up
-Rolled down uniforms still protect your torso
-Rolled up sleeves still protect your arms
-Chameleon gear not cloning body protection flags

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:cl:
fix: Fix unable to eat when mask is down
/:cl:

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Author: Sorrowfulwinds

code/game/objects/items.dm

@@ -824,7 +824,8 @@ modules/mob/living/carbon/human/life.dm if you die, you will be zoomed out.
 
 //* Flags *//
 
-/obj/item/proc/set_body_cover_flags()
+/obj/item/proc/set_body_cover_flags(new_body_cover_flags)
+	body_cover_flags = new_body_cover_flags
 	inv_inside.invalidate_coverage_cache()
 
 //* Interactions *//