Expand automated testing for main functionality

[alexbainter]

Resolves #79.

• Adds end-to-end testing with Playwright for the feedback forms on the index page, article list page (when there are multiple matching results for the user's query), and the article page.
• Updates the index page tests to ensure there's at least one datatype, and then programmatically check each datatype's source and destination combinations to ensure they are all valid.
  • I know we discussed that we might not need to do this, but I was basically done with it by the time we had that conversation :sweat_smile:. I do think there's value here because this is the primary functionality of the site and it requires client-side JS, so testing it in a browser environment makes sense.
  • Even with this in place, all the tests run in a little over 30 seconds

[alexbainter]

Updated to use a factory! https://github.com/dtinit/portmap/pull/89/commits/05c1ca2c3aff91416a0b9e5975b8f8b50d57503e