[Maps] Draw bounds to filter data does not allow for using more than 1 index

[eddieturizo]

Describe the feature:
It would be useful to be able to query more than 1 index when using the Draw bounds to filter data within the Maps app.

Describe a specific use case for the feature:
Perform geospatial queries and return all data sets on the map that fall within those bounds.

[elasticmachine]

Pinging @elastic/kibana-gis (Team:Geo)

[nreese]

Closed by #100735