[dagit] Crag: Add /jobs
Summary: Add /jobs as a valid workspace route. For users in the Crag flag, redirect /pipelines routes to /jobs.
View Dagit with flag turned on, verify that all /pipelines routes redirect to /jobs routes.
View Dagit with flag turned off, verify that all /pipelines routes behave as before, and that /jobs routes also work.
Reviewed By: bengotow
Differential Revision: https://dagster.phacility.com/D8316