Fixes a small bug with shields that stopped them from working (#3704)

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## About The Pull Request

minor oversight

## Changelog

:cl:
fix: shields work as intended again
/:cl:

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Signed-off-by: Theos <[email protected]>

code/game/objects/items/shields.dm

@@ -35,7 +35,7 @@
 		final_block_chance += 30
 	if(attack_type == LEAP_ATTACK)
 		final_block_chance = 100
-	. = .()
+	. = ..()
 	if(.)
 		on_shield_block(owner, hitby, attack_text, damage, attack_type)