Several Ninja Suit power cell upgrade fixes. (#32902)

* Fix several jank issues with space ninja cell upgrades.

* Rework the code to comply with maintainer request.

* Fix some naming convention & formatting errors.

* Change from a custom check to an item whitelist to avoid power cages from fitting.

* Make the EntityUid of GetCellScore non nullable.

* Remove a line from a previous solution to the above problem I forgot to remove.

* Fix the magic number issue.

Resources/Prototypes/Entities/Clothing/OuterClothing/suits.yml

@@ -187,6 +187,9 @@
         name: power-cell-slot-component-slot-name-default
         startingItem: PowerCellSmall
         disableEject: true
+        whitelist:
+          tags:
+            - PowerCell
 
 - type: entity
   parent: ClothingOuterBase