fix(coturn): explicitly null rollingUpdate field alongside Recreate strategy

Server-side apply left the old RollingUpdate defaults (maxSurge/maxUnavailable)
on the live object from before strategy.type was ever set explicitly, which
the API rejects when combined with type: Recreate. Explicit null clears it.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/production/coturn.yaml

@@ -70,6 +70,7 @@ spec:
   # can never schedule (port conflict). Recreate kills the old pod first.
   strategy:
     type: Recreate
+    rollingUpdate: null
   selector:
     matchLabels:
       app: coturn