Zoning E2E Test + E2E Improvements

[ChristianAtDell]

Description

The primary goal of this PR is to add an E2E test scenario (and robust testing script) that covers the new zoning work. In addition to that, some improvements were added to the E2E test suite.

1. All custom tests in E2E scenarios are now part of an 'array' of custom tests for their scenario, and can be selected individually. This allows for multiple custom tests to be run per scenario, which was necessary for adding and removing zone labels to k8s nodes. Future scenarios added will need to have their custom tests indented inwards to be part of an array, but legacy support for the previous 'run custom test' E2E step was left intact.
2. A new way of deploying secrets as a part of E2E tests was introduced, that creates the secret by reading in the template file, editing the string in-memory, and deploying from that string. This was necessary because the previous way templates were used, editing in place, created an impossible scenario to restore from in our testing: if any two template keys had the same value, it was impossible to reverse the string replacement that was done.

GitHub Issues

List the GitHub issues impacted by this PR:

GitHub Issue #
dell/csm#1613

Checklist:

• I have performed a self-review of my own code to ensure there are no formatting, vetting, linting, or security issues
• I have verified that new and existing unit tests pass locally with my changes
• I have not allowed coverage numbers to degenerate
• I have maintained at least 80% code coverage
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• I have maintained backward compatibility
• I have executed the relevant end-to-end test scenarios

How Has This Been Tested?

E2E scenario has been run standalone. It passes, though that does not actually test zoning yet, as zoning work is not completed.

[donatwork]

Have you tested this with special shell characters in fileString, e.g. dollar signs and exclamation marks.

[ChristianAtDell]

Definitely exclamation marks, because one of our test secrets includes one in a field. Otherwise, no comprehensive testing was done on it, but I'm not too worried about it-- this is just running e2e tests using controlled templates and provided inputs.

[ChristianAtDell]

Ignore the commit to revert, I went to click 'delete branch' and hit 'revert' instead, which opened a new branch with a revert commit. I've deleted the branch.