remove unnecessary reloads

[hiiiideepak]

There are many requests where page reload can be avoided.
Like

1. when clicking on close/open label of issues changes and page is reloaded while this reload can be avoided by using javascript to change open to close etc on GUI 😄
2. on deleting prs/issues there is a page reload which can be avoided by hiding that object using javascript.

every page reload removal gets ~30 points 😄
create different prs for each such solution

[hiiiideepak]

3. Remove page reload when any mentor verify/reject a pr.
4. Remove reloads on delete action on prs available at student/mentor profile.

[jarvisdev]

4 done already in PR #122
2 done in PR #129