qa/tasks/ceph: fix "ceph mgr module enable" command

This was typoed in commit 9d485ae ("qa/tasks/ceph: provide
configuration for setting configs via mon") and went unnoticed likely
because 3-snaps/yes.yaml in fs:workload is the only user of the new
mgr-modules stanza so far and fs:workload suite runs exclusively on
cephadm.

Signed-off-by: Ilya Dryomov <[email protected]>

Author: idryomov

qa/tasks/ceph.py

@@ -376,7 +376,7 @@ def module_setup(ctx, config):
            cluster_name,
            'mgr',
            'module',
-           'emable',
+           'enable',
            m,
         ]
         log.info("enabling module %s", m)