Make github actions more feature complete

[TomHellier]

@liyinan926 Please before merging this change, could you look at adding the gcr.io registry secrets into github secrets? Please see this section of the github workflows.
https://github.com/GoogleCloudPlatform/spark-on-k8s-operator/blob/master/.github/workflows/release.yaml#L31-L39

This change renames the github workflows to be clearer about their purpose, and adds a set of tests which
aim to force developers to increment the appVersion if they have changed anything with the spark-operator docker container
or the chart version if they have updated the chart.

These changes should hopefully enforce that docker images & helm charts are released when changes are made to them, and remove manual steps required by @liyinan926

Main Changes:

• Added multiple github workflows to test
  • build-api-docs
    • fails if the apis change
    • generates the documentation, and fails the committed api-docs.md is different
  • build-sparkctl
    • ensures sparkctl builds sucessfully
  • build-spark-operator
    • ensures the spark-operator container can build
    • passes unit tests
    • no issues with govet
    • no issues with gofmt
    • Requires an update to the appVersion of the helm chart if changes to the docker container are in the PR
  • build-helm-chart
    • Builds the helm chart
    • produces the documentation
    • lints the chart
    • asserts that the chart version changes if any helm changes have occurred
    • installs the helm chart into a minikube cluster
    • checks for crd drift between chart and operator
  • integration-test
    • builds a local spark-operator, installs it into minikube
    • commented out integration test, while The e2e integration tests are currently broken #1416 is not done

[liyinan926]

This is awesome! Thanks for contributing!