Enable auto_approve for hello-world

[katrinleinweber]

I am unsure whether this is necessary, because #98 has a checkbox for this, but later says We've currently made any hello-world exercises auto-approved in the backend.

Either way, shall we set other exercises to "auto_approve": true?

[jonmcalder]

Thanks for following up on #98!

I interpret it as saying that auto_approve: true should be set on the first exercise if it isn't hello-world (and that hello-world will be auto-approved by default), but agree that's it's better to be explicit just in case.

I don't think we need/want to auto-approve anything else just yet though.