[dagit] Enable extended search for global search
Set useExtendedSearch: true on Dagit global search: https://fusejs.io/examples.html#extended-search
This should enable using spaces as "AND" operators, which should improve searching with multiple text tokens.
Test Plan: Search for "dash cost", verify that dashboards > cost_dashboard asset appears in results.
Reviewers: bengotow, prha, sashank
Reviewed By: bengotow
Differential Revision: https://dagster.phacility.com/D7324