Test Pilot Heartbeat Prompts

Currently in Test Pilot, we drop a Heartbeat rating bar to prompt our testers to rate an experiment they are using.

Originally, once the user inputted a rating, the bar would disappear and a new tab would open with a prompt to fill out a survey.

Having the survey prompt open in a new active tab is pretty annoying, so I've now included the survey prompt in a "Thank you" bar the user receives after rating an experiment.