[ML] Unable to (re)start datafeed for an apm anomaly detection job

[kpatticha]

Kibana version: 8.0

Elasticsearch version: 8.0

Describe the bug:
I created the job and it was running as expected. Then I stopped the datafeed and started it again
I got 200 once I started the datafeed but on refresh the job state is closed and the datafeed is stopped.
After following the above steps, there is a warning that "Datafeed look back retrieved no data"

Steps to reproduce:

start-datafeed.mov

Expected behavior:
I would expect to receive a failed message once I start the datafeed

[kpatticha]

it could be an env issue