Change "SUBMIT" button text and "FINALISE SUBMISSION" button color for clarity

[pakshuang]

CS1010S TA here. Thanks for all the great work that y'all do to improve the platform for learning.

I would like to suggest an improvement in the UI of assessments: Instead of "SUBMIT", the button should read "RUN" to indicate that it runs and checks the students code. This is to improve the clarity of what the button does, as well as help differentiate it from the "FINALISE SUBMISSION" button. Additionally, it would be great if "FINALISE SUBMISSION" was in a different color, such as orange which is a different color from "SUBMIT" and also a color that indicates "warning" or "alert". The goal is to prevent premature finalizations. Also, maybe the "FINALISE SUBMISSION" button should only be at the last question for assessments with multiple pages.

I hope that this change is easy to implement on the current platform, as well as the upcoming react platform. Thanks!