Implement Github Workflow generation for building and deploying a function to a k8 cluster.

[twoGiants]

Summary

Extend the func cli with the capability to generate a GitHub Actions workflow setup (with yaml file and directory) in the given function repo.

The workflow should contain:

• a checkout of the code
• get/setup of the func cli using the knative-func-action
• and running func deploy|func deploy --remote

The user should have the option to create the workflow with different configurations for a local build in the Github action runner or a remote on-cluster build.

Subtask of #2024.

Resources

• sample workflow: https://github.com/functions-dev/templates/blob/main/.github/workflows/invoke-all.yaml
• func github action: https://github.com/gauron99/knative-func-action

Pull Requests

• Fix typos in comments and documentation across the codebase. #3257
• Refactor: extract common loader/saver interfaces (Github Workflow generation prep). #3262

[twoGiants]

/assign

[twoGiants]

/kind enhancement