Remove manila tests from blacklist
Remove manila tests from blacklist

The NFS bug (bsc#1137262) that was affecting these tests has been
resolved, and moreover we switched the manila service VM to SLE15, so
these tests should work now.

SUSE-Cloud/automation,SUSE-Cloud/automation,gosipyan/automation,SUSE-Cloud/automation,gosipyan/automation,SUSE-Cloud/automation,gosipyan/automation,gosipyan/automation