As a part of the porting process, remove unused imports and
markers, remove non-next_gating tests and tests marked with
`required_features("!consistent-topology-changes")` marker.
Remove `test_permissions_caching` test because it's too
flaky when running using test.py
Also, make few time execution optimizations:
- remove redundant `time.sleep(10)`
- use smaller timeouts for CQL sessions
Enable the test in suite.yaml (run in dev mode only)
