This test accesses system indices for 2 reasons.
First, it creates a filter that has a different type. This was done
to assert that filter is not returned from the APIs. However,
now that access to the `.ml-meta` index is restricted,
it is not really a concern.
Second, it creates a `.ml-meta` index without mappings to test
the get API does not fail due to lack of mappings on a sorted field,
namely the `filter_id`. Once again, this test is less useful once
system indices have restricted access.
Relates #62501
Backport of #63111
46c3973400