Add function `is_test_allowed` for specific OS and version.

Some containers are not available for Helm Charts
and therefore the test should be skipped.

The Minimal containers that are allowed are mentioned
in Red Hat Container Catalog see. https://catalog.redhat.com/en/search?searchType=Containers&q=python+minimal&p=1

Signed-off-by: Petr "Stone" Hracek <phracek@redhat.com>