Missing "run code" hotkey for manual graded programming questions

[cysjonathan]

#4028 adds hotkey for autograded assessments But for manual graded programming questions, hotkey does not exist.

This probably raises a separate UX issue, whether we should have a hotkey to navigate forward/back especially for manual graded questions. e.g. when a manually graded assessment has 10 mcq questions, users will be forced to click on answer, then click on qns bubble, repeat 10 times.