Finishing the deprecation of the skip_mode function in favor of
pytest.mark.skip_mode. This PR is only cleaning and migrating leftover tests
that are still used and old way of skip_mode.
Closesscylladb/scylladb#28299
Function skip_mode works only on function and only in cluster test. This if OK
when we need to skip one test, but it's not possible to use it with pytestmark
to automatically mark all tests in the file. The goal of this PR is to migrate
skip_mode to be dynamic pytest.mark that can be used as ordinary mark.
Closesscylladb/scylladb#27853
[avi: apply to test/cluster/test_tablets.py::test_table_creation_wakes_up_balancer]
The test test_multiple_unpublished_cdc_generations reads the CDC
generation timestamps to verify they are published in the correct order.
To do so it issues reads in a loop with a short sleep period and checks
the differences between consecutive reads, assuming they are monotonic.
However the assumption that the reads are monotonic is not valid,
because the reads are issued with consistency_level=ONE, thus we may read
timestamps {A,B} from some node, then read timestamps {A} from another
node that didn't apply the write of the new timestamp B yet. This will
trigger the assert in the test and fail.
To ensure the reads are monotonic we change the test to use consistency
level ALL for the reads.
Fixesscylladb/scylladb#24262Closesscylladb/scylladb#24272
