Use allow_no_indices: true to avoid failures after manually deleted indices

If someone manually deletes an index via Kibana using DELETE /my_index_rollover_2024-01, we see failures from EG because it still attempts to search against the now-deleted indexes. Specifically, we see errors like no such index [my_index_rollover_2024-01].

This is caused by EG caching the full list of indices and using that when it makes queries against OpenSearch.

From discussion, the solution would be to set allow_no_indices: true (docs link) to avoid these errors after indices are manually created.