`403 Forbidden Error: Server access requires a VPN connection.` too aggressive when polling

When polling a job, `403 Forbidden Error`'s severity should drop down to a warning. Maybe there was a hiccup on the VPN, having to hunt for the job id to resume the poll is annoying.

Start by tracing the job-polling path that handles a `403 Forbidden Error` response. The change is done when a VPN-related 403 is treated as a warning and polling can resume without manually hunting for the job ID; the payload does not name a file or test to run.

Written by the indexing model from the issue text.