The commit 1ce2f04 tried to merge multiple SUSE OS checks including
"openSUSE Leap" and "openSUSE Tumbleweed" into a single SUSE, but
that was a perfect change.
Then the commit c16efc9 tried to fix it for "openSUSE Leap", but it
didn't take care of "openSUSE Tumbleweed".
Then this adds "openSUSE Tumbleweed" to the OS check.