[BUG] index_template action type is not part of cluster-permissions check even though template is.

[DarshitChanpura]

The part of code which evaluates an action to be of cluster permission type here is missing the logic to check for index_template action type.

Behavior before change:
All the actions with pattern indices:admin/index_template/ are not evaluated as cluster-level permissions even though by design it should. This, alongwith the miss in documentation website, mislead users to provide this permission as index-level when trying to fix it.

Expected behavior after change:
All the actions with pattern indices:admin/index_template/ should be evaluated as cluster-level permission.