Fix the Review Apps config syntax

This was inadvertently broken due to a wrong suggestion applied at
https://gitlab.com/gitlab-org/gitlab/-/merge_requests/57782#note_540576935Signed-off-by: Rémy Coutable <remy@rymai.me>

scripts/review_apps/base-config.yaml

@@ -136,8 +136,10 @@ postgresql:
   metrics:
     enabled: false
   resources:
+    requests:
       cpu: 600m
       memory: 1000M
+    limits:
       cpu: 1300m
       memory: 1500M
 prometheus: