batches: Prevent batch spec with mounts for SSBC
Created by: Piszmog
Part of #31790 (closed).
Adds checks to prevent a batch spec with a mount
in a step
from being processed when running server-side batch changes.
-
CreateBatchSpecFromRaw
called from UI SSBC -
UpsertBatchSpecInput
called fromsrc batch remote
command
Test plan
Go unit tests and manual testing.