testing: fix column acl test

[shollyman]

test_create_table_with_policy in the system tests is currently broken because it expects weak validation on the backend. This is no longer the case, and thus the test fails.

Two things:

• skip the test for now
• use this issue to track refactoring the test to use a real taxonomy and tags (means datacatalog integration)

[shollyman]

It seems there's already a test_create_table_with_real_custom_policy in the tests, so its just a matter of removing the bad test.