E2E Tests

In order to build confidence in deploys, we should expand our test suite to include E2E tests that hit the key components of the app and verify they work.

This is a placeholder issue while waiting on the manual QA plan in https://app.zenhub.com/workspaces/maple-main-629389aa02e9d200139c90b8/issues/gh/codeforboston/maple/1504 - Once we have that, we can use it to start prioritizing tests to write and breaking them out into separate issues.