Lowers antag amount for Grimbly Pop Balance. (Grimbly-Station#124)

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# As the title says.

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:cl:
- fix: Lowers antag amount for Grimbly Pop Balance.

Resources/Prototypes/GameRules/roundstart.yml

@@ -147,7 +147,7 @@
   - type: AntagSelection
     definitions:
     - prefRoles: [ Traitor ]
-      max: 12
+      max: 6 ##Was 12. Made it 6 for Grimbly Pop Balance.
       playerRatio: 10
       lateJoinAdditional: true
       mindComponents: