Add tests for bucket quota end points

[cniackz]

Fixes https://github.com/miniohq/engineering/issues/393
Fixes https://github.com/miniohq/engineering/issues/394

Add tests for Bucket Quota end points in Console API

Coverage in master is:
* coverage: 26.5% of integration tests
* coverage: 21.2% of unittest in restapi
* coverage: 42.3% of both areas above

Coverage in get-bucket-quota-1-test branch:
* coverage: 27.8% of integration tests
* coverage: 21.2% of unittest in restapi
* coverage  43.6% of both areas above

To get coverage: https://docs.google.com/document/d/1tEBMSmpoCftvtgUYjCSzAGqWM1T-1OsHk7AxvUoq0VM/edit?usp=sharing