Fix tox in container
Fix tox in container

The tox wasn't able to install dependencies, because of missing gcc.

Signed-off-by: Michal Konečný <ee90a345d5d5a9b1fcc0d90446d9d8a36f3b88d1@redhat.com>

fedora-infra/the-new-hotness,fedora-infra/the-new-hotness