feat:View and modify status of all the form submissions

## Description

As an Admin, I need to be able to view all the form submissions made and update individual form status.

Changes in the mock: Add a header row, with a checkbox (with all rows selected), Applicant Name, GitHub Username, Zulip Username, Status.

## Mock
https://drive.google.com/file/d/1JuZetC0y8RCQ-72jFrehLSs-8HfTY74A/view

## Acceptance Criteria
### Update [Required]
- [ ] Admin is able to view submissions
- [ ] Admin is able to add status: accepted/waitlist/rejected/pending to a form
- [ ] UI should follow the mock with mentioned changes
- [ ] Write tests for it

## Definition of Done
- [ ] All of the required items are completed.
- [x] Approval by 1 mentor.

## Estimation
1-2 days