Follow-up from "Resolve "Can't set "never" as an environment auto_stop_in value""

The following discussion from !90514 (merged) should be addressed:

• @eric.secules started a discussion:

  Sorry in advance if I should not be commenting on a merged PR, but I thought it made more sense to comment here...

  If someone set "never" and self.auto_stop_at was currently defined, it wouldn't get unset.