* return empty list instead of rpc error when no records found for staking delegations
* fix grpc query DelegatorDelegations tests
* remove response code tests for staking delegations
* fix failing tests
* change staking delegations response code to 200 in grpc test
* add staking delegations response code tests to TestQueryDelegatorDelegationsGRPC
* add address without delegations testcase
* add changes to grpc query tests of delegatorDelegations
* remove getRequest unused function from x/staking/client/rest/grpc_query_test.go
* minor fixes
* add testcases for request with no delegations
* address review comments
* add changelog
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>