Upgrade Nightwatch (v1 -> v2) and switch from Travis to GH Actions

[fryjordan]

• Upgrade Nightwatch from v1 -> v2
• e2e Selenium tests are currently being run in a Docker container. This is both unnecessary and a nuisance when debugging. This PR includes changes to switch from running Selenium in a Docker container, to locally.
• There are limitations to using Travis, including free compute limits, and run time duration. As a result, it is preferable to use GitHub Actions. This PR includes changes to move from Travis to Github Actions.