UI: updated mentorship relation accepted mock and added it

[vj-codes]

Description

Added UI mock so that I can get reviews and then proceed to code it.

Fixes #769

Type of Change:

• User Interface
• Documentation

Screenshot of mock -

Checklist:

• My PR follows the style guidelines of this project
• I have performed a self-review of my own code or materials

Code/Quality Assurance Only

• My changes generate no new warnings
• New and existing unit tests pass locally with my changes

[codecov]

Codecov Report

Merging #828 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #828   +/-   ##
========================================
  Coverage    95.84%   95.84%           
========================================
  Files           95       95           
  Lines         5200     5200           
========================================
  Hits          4984     4984           
  Misses         216      216           

[SanketDG]

Looks good, I am hoping @isabelcosta will provide more insights on the copy.

[isabelcosta]

@vj-codes thank you for participating on OSH!
I'll close the issue as we're going to discuss designs for emails altogether and then implement changes. I will add this PR to our Wiki :)