flake: IndexStatus

Created by: efritz

Example build: https://buildkite.com/sourcegraph/sourcegraph/builds/142037#fae897b1-9931-42ec-864b-34172a3cc879

FAIL | IndexStatus (1.73s)
FAIL | 	github.com/sourcegraph/sourcegraph/internal/database/migration/store	19.704s

dbtest.go:91: testdb: postgres://postgres:[email protected]:5432/sourcegraph-test-12377496463070805422?sslmode=disable&timezone=UTC
store_test.go:524: expected index status
dbtest.go:101: DATABASE sourcegraph-test-12377496463070805422 left intact for inspection

This happening in db-backcompat tests but I suspect it may be a general flake.