implement "delete a commons" functionality in commonsController.java

[rsdharmaji]

Overview

the delete method is added to the commons controller

Issues Addressed

closes #32

Details

delete method supports an id for deletion, and throws an EntityNotFoundException if deleting nonexistent commons.
ADMIN authentication is required to use the delete method.

here is an "after" image:

[codecov]

Codecov Report

Merging #44 (ea552fd) into main (fbf08f8) will increase coverage by 0.51%.
The diff coverage is 100.00%.

@@             Coverage Diff              @@
##               main      #44      +/-   ##
============================================
+ Coverage     78.78%   79.30%   +0.51%     
- Complexity       59       61       +2     
============================================
  Files            51       51              
  Lines           396      401       +5     
  Branches         10       10              
============================================
+ Hits            312      318       +6     
+ Misses           84       83       -1     

Impacted Files	Coverage Δ
...156/happiercows/controllers/CommonsController.java	100.00% <100.00%> (ø)
...b/cs156/happiercows/controllers/ApiController.java	100.00% <0.00%> (+14.28%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update fbf08f8...ea552fd. Read the comment docs.

[jacksoncooper]

Use proper HTTP statuses when the server replies later.

changes implemented in last commit

[Jacqueskim]

LGTM

[kheff16]

Needs rebase or merge with main but otherwise lgtm

[jacksoncooper]

I don't think we broke anything merging.

[jacksoncooper]

#52 affects this.

[jacksoncooper]

This patch doesn't work, unfortunately.

issue unfixable.