Create cypress tests for blog spec

[laylark]

• Please check if the PR fulfills these requirements

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

• What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)
  Additional Cypress tests for blog pages.

• What is the current behavior? (You can also link to an open issue here)
  A portion of Review test coverage and augment / strategize as needed. #85.

• What is the new behavior (if this is a feature change)?
  N/A.

• Does this PR introduce a breaking change? (What changes might users need to make in their application due to this PR?)
  No.

• Other information:
  In order for Cypress to follow the blog links, I needed to wait for a pretty large period of time. Otherwise, the remainder of the test after the link clicked would not follow through to the next page. I am curious if this is related to how Next.js handles some of the routing. If you have any thoughts or advice on how to improve this, let me know!

[zenlex]

@laylark I think this looks great! Thanks for the tests! I am curious - did you build for production before you ran the tests or were you running them against the dev environment? I'm realizing I don't force a production build with the cypress script currently. If you were running the tests against the dev server I suspect that was the reason for the slow load times. Good catch. Either way I'll update that or add another script to run yarn build && yarn start && cypress run. Also curious if you were running it with the cypress UI or in headless mode? (There's scripts for both in the package.json if you didn't see them)

[zenlex]

Nice work!