couchbase - clean up test suite

• Remove the check_if_mock_unstable() method
• Add ability to skip tests if using the mock and the mock does not support feature prior to making a connection (save some time and save connections)
• Utilize get_environment class method for entire test suite

These changes will serve as the baseline for cleaning up the acouchbase test suite (i.e. it follows the same pattern of setup/teardown with the exception of needing to utilize async/await syntax). These changes will also server as a baseline for getting the txcoucbhase test suite setup.