[chore] refactor ghwf functional tests go dependency caching

[jvoravong]

Description:

This PR optimizes the functional test workflow by properly implementing go dependency caching, which was previously not utilized correctly. The update results in significant performance improvements by reducing test completion time and saving on CPU and network resources.

Changes:

• Implemented caching for functional test execution and removed prevous caching implementation.
• Added make action to run functional tests to help utilize caching.
• Standardized the version of Go used in testing.
• Added better documentation.

Performance Improvements:

• Without caching:

  • Step: Run functional-tests
  • Link to run
  • Completion time: 4m34s

• With caching:

  • Step: Run functional-tests
  • Link to run
  • Completion time: 3m1s

Highlights:

• The caching optimization reduces the step that previously took the most time in the functional tests by about 1m30s, resulting in a 33% performance increase in time to completion for the step.
• Overall, the full github workflow that runs this test had it's time reduced from approximately 5m45s to 4m15s, yielding an overall 26% improvement in test run time.

[jvoravong]

Looks like some of the eks upgrade tests are failing. Checking it out, can't tell yet if it is due to a previous existing issue or due to the changes in this PR.

[jvoravong]

There was an issue with our eks upgrade tests where the environment wasn't cleaned up before the tests ran. This caused failures when the environment was left in an inconsistent state from a previous test run, often due to a hard failure of a previous test run. I added a quick 2-line fix to ensure proper cleanup before each test.

[atoulme]

LGTM!