[Upgrade Testing]Not able to setup tier limit when upgrade from 6.6.5 to 7.1.0

Steps to reproduce:

1. Setup a 4 node cluster kv-kv-n1ql-query with 6.6.5. Load data into it and create some indexes
2. Offline upgrade all 4 nodes to 7.1.0-2074
3. Setup tier limit on _default scope

   curl --location --request GET 'http://10.112.205.103:8091/pools/default/buckets/test_bucket/scopes' \

   --header 'Authorization: Basic QWRtaW5pc3RyYXRvcjpwYXNzd29yZA==' \

   --header 'Content-Type: application/x-www-form-urlencoded' \

   --data-urlencode ' name==_default&limits={"index": {"num_indexes":5 }} '

   Requested resource not found.

1. I ran through Python request client but above curl gives same error.

   2022-01-27 13:02:01,652 - root - ERROR - POST http://10.112.205.103:8091/pools/default/buckets/test_bucket/scopes body: name=_default&limits={"index": {"num_indexes":5 }} headers: {'Content-Type': 'application/x-www-form-urlencoded', 'Authorization': 'Basic QWRtaW5pc3RyYXRvcjpwYXNzd29yZA==', 'Accept': '*/*'} error: 404 reason: status: 404, content: b'Requested resource not found.\r\n' b'Requested resource not found.\r\n' auth: Administrator:password