The introduction of a default index for timeseries (SERVER-66689) currently expects the index to have the default collation, even if the collection is specifically created with a non-simple collation.

The timeserie_index_partial.js tests currently verifies this behaviour for a collection with non-simple collation with the "extraIndexes" being the expected the index fields set here.
in case a moveCollection run in between the creation and the check of the collection, the check will fail as the index now contains the field "collation".

The goal of this ticket is to investigate whether is ok for the collation field to be present and in case fix the TODOs