test: add test cases to confirm output for PinnedCodes

[Kynea0b]

Description

PinnedCodes: TestQueryPinnedCodes

Add a test case because we have not tested for pagination.

message QueryPinnedCodesResponse {
  repeated uint64 code_ids = 1 [ (gogoproto.customname) = "CodeIDs" ];
  // pagination defines the pagination in the response.
  cosmos.base.query.v1beta1.PageResponse pagination = 2;
}

spec:
https://github.com/CosmWasm/wasmd/blob/main/proto/cosmwasm/wasm/v1/query.proto#L236

Checklist:

• I followed the contributing guidelines and code of conduct.
• I have added a relevant changelog to CHANGELOG.md
• I have added tests to cover my changes.
• I have updated the documentation accordingly. (not needed)
• I have updated API documentation client/docs/swagger-ui/swagger.yaml (not needed)

[170210]

Please add changelog in CHANGELOGS.md

[170210]

LGTM