[dagit] Break apart Asset materialization query
When viewing an asset, a single query is performed to retrieve 200 asset materializations. If this is slow, it blocks the entire page from rendering anything useful.
Instead of this, break it into two queries: one to retrieve the latest materialization (limit: 1) and one to retrieve the latest 200. This way, the latest materialization information can be rendered while the rest is still being retrieved.
Test Plan: View an asset, verify that the details and list/graph render properly.
Reviewers: bengotow, sandyryza, prha
Reviewed By: prha
Differential Revision: https://dagster.phacility.com/D7355