fix: use latest version aurora postgresql

https://repost.aws/questions/QU586x8RblToKSH-CBeF8B2g/aurora-end-of-standard-support-date-for-postgresql-15-4

Author: stxkxs

src/main/resources/production/v1/druid/setup/storage.mustache

@@ -94,7 +94,7 @@ metadata:
       requireEachIncludedType: true
     removalPolicy: destroy
   databaseName: druid_metadata
-  version: 15.4
+  version: 17.6
   storageType: aurora_iopt1
   writer:
     name: metadata-writer