Add reviewers-grundfos as an official review member (#33986)

This will allow  https://github.com/orgs/project-chip/teams/reviewers-grundfos/members to count as a SDK official reviewer for consensus purposes of 2+ companies per review.

Author: andy31415

.pullapprove.yml

@@ -133,6 +133,14 @@ groups:
             teams: [reviewers-google]
         reviews:
             request: 10
+    shared-reviewers-grundfos:
+        type: optional
+        conditions:
+            - files.include('*')
+        reviewers:
+            teams: [reviewers-grundfos]
+        reviews:
+            request: 10
     shared-reviewers-irobot:
         type: optional
         conditions: