Adding better exception for when blocked by bot protection

[andre-c-andersen]

Adding this because it was hard to debug why I didn't get any transcripts.

A bot restricted HTML text looks like this:

"playabilityStatus":{"status":"LOGIN_REQUIRED","reason":"Sign in to confirm you’re not a bot"

A healthy HTML text looks like this:

"playabilityStatus":{"status":"OK"

I was restricted when deployed using a python container on DigitalOcean's App Platform.