Time zone resets on Add New Feedback Session if form validation fails #2463

For #2463 
Hmm, I guess I can add a check to remove the blank option if it exists instead.

Should I put the constant in common.js or instructorFeedbacks.js? I noticed there's a TODO in line 1 of instructorFeedbacks.js: 
//TODO: Move constants from Common.js into appropriate files if not shared.