Add Basic Cypress Testing To Missing Apps

[alexfinnarn]

Now that there are more Dependabot PRs, it would be nice to have at least one system test per repo. This way, we'd at least know the main features of the app aren't broken with each dependency update. Since the tests broke on giving-frontend, I've just been blindly merging them in and dealing with any issues later.

Adding Cypress via GH Actions is standardized and this shouldn't take too much time. All of these apps are public-facing and require no login.

• [x] giving-frontend - Due to the work left for payment providers and that potentially switching, I removed the checkout tests that were already written. Those tests will be put back in when the payment provider is finalized.
• [x] essential-cu
• [x] crowdfunding-cu
• [x] cu-giving

Do Later:

• giving-backend - Might as well wait until the switch in Auth to Devise since pretty much all tests should be logged in.

[alexfinnarn]

Looks like I already have an issue for crowdfunding: https://github.com/CUCentralAdvancement/crowdfunding-cu/issues/21

[alexfinnarn]

Hooray, I was able to get cu-giving testing fixed as well so all deployed apps will have automated testing run before deployments and/or merging PRs.

[alexfinnarn]

I added tests that all passed initially, but it will take some PRs to see if they run reliably or need some more modifications.

[alexfinnarn]

enough PRs have passed on essential-cu and crowdfunding that I will mark this issue as done. The giving-frontend tests probably need updated as the Fund model and search results change to include license plate, write-in funds and other small changes.