FEATURE: GET all recommendation requests endpoint for Admin

[ameymwalimbe]

Have you updated the title?

• I have updated the issue's title.

As a...

Admin

I can...

I get all recommendation requests in the application

So that...

I can see all recommendation requests in the application

Discussion

There are three users in this application: students, professors, and admins.

Students submit requests to professors and professors can only see requests submitted directly to them. On the flipside, admins should be able to see ALL requests.

After this issue, you should be set to work on #5

Acceptance Criteria

Backend:

• There should be an endpoint /api/recommendationrequest/admin/all on swagger
• The endpoint only works for admin

Implementation Todos

• Add the /api/recommendationrequest/admin/all endpoint to RecommendationRequestController.java