Remove 3.14-minimal from `enable_epel_repo`.

Checking Helm Charts for version 3.14 and 3.14-minimal
is available onlu for RHEL9 and RHEL10. No
condition is needed.

We want only minimal images for C10S/RHEL10,
so we know if there is a market for the full container images.

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