Status code tests

[Benehiko]

Related issue(s)

These are complete tests written to validate the updated handlers do in fact return status code 303 instead of 302.

These tests should be enough to continue implementing tests for:

• Settings
• Recovery
• Registration
• Verification

Checklist

• I have read the contributing guidelines.
• I have referenced an issue containing the design document if my change
  introduces a new feature.
• I am following the
  contributing code guidelines.
• I have read the security policy.
• I confirm that this pull request does not address a security
  vulnerability. If this pull request addresses a security. vulnerability, I
  confirm that I got green light (please contact
  [email protected]) from the maintainers to push
  the changes.
• I have added tests that prove my fix is effective or that my feature
  works.
• I have added or changed the documentation.

Further Comments