Update to solution code functionality

The feature which allows users to get the solution to an exercise after submitting incorrect code a few times has received a UI update.

If a CodeEditor exists in an exercise (as with most exercises), then the modal will not pop up immediately after the nth attempt. Instead, a new button will appear in the CodeEditor’s footer. This makes option to get the “solution code” less intrusive, and coders can continue to work away uninterrupted if they’d prefer to keep trying.

Please note that this new feature is only visible on exercises with a CodeEditor. Also, exercises that have a double-width CodeEditor rely on the original modal flow rather than the new button flow. This is because the Solution button would be overlapped by our Pro Advisor Intercom button in those cases.