Update github action to use specific crystal versions and add scheduled action

[matthewmcgarvey]

Current Actions

One action that is triggered by pull requests and commits to master. It has 3 jobs that all run against ubuntu and installs whatever the latest version of crystal is. The 3 jobs are:

• Verify chrome when it starts the chromedriver process itself
• Verify chrome with already running chromedriver process
• Verify firefox

Desired Actions

One action to verify pull requests and pushes to master.

• Same as above but run in crystal's provided docker containers and use the expected version

One action that is scheduled to run every week.

• Run with Chrome only where it starts its own process
• Use the nightly version of Crystal

[matthewmcgarvey]

Resource: https://jasonet.co/posts/scheduled-actions/

[matthewmcgarvey]

I had to drop testing other browsers but I did switch to a specific Crystal version in github actions. Not going to worry about scheduled actions right now