Fix flaky tests

[zeina-idris]

• Fixed most of the obvious flaky tests by adding { timeout } to most buttons that call to the backend
• CreateCusomer() and Login() are now in different commands in commands.js
• Show loading animation in cart and order list #160 Handled "isLoading" case in:
  • Cart
  • Order list
  • Product list
• Added graphqlTimeout option in cypress.json configuration.

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Checklist

• E2E tests

[lauraluiz]

There are very important improvements in this PR that will for sure make tests more reliable. And tests are already green, so flaky tests are not so annoying as they were. What I want to say with this is that whenever you are not 100% sure a timeout helps, remove it. If then you identify a test that is flaky and this is the cause, put it back. But adding timeouts that are not necessary will harm the tests more than not having them.

Looking forward merging this PR to make e2e testing sturdy 💪

[lauraluiz]

I didn't manage to review everything today, more tomorrow ;)

[zeina-idris]

ProductList component was failing in the unit test, because it's expecting products!
So I start the component with v-if=products then we have all the cases in this order:
v-if=isLoading
v-else-if=products.results.length
v-else bad case
Tested it everywhere and works like a charm.

[zeina-idris]

👍