batches: add feature flag for hiding `Run Batch Spec` button
Created by: BolajiOlajide
Part 1 #36920 (closed)
Test plan
- Spin up a sourcegraph instance without any active executor
- Create a batch change
When the flag 'hide-run-batch-spec-for-mi'
is set to true, the run server-side
button is hidden for MIs that have no executor setup.
App preview:
Check out the client app preview documentation to learn more.