Cachability of k8s_test_setup is dependent on the checksum of kubeconfig file

[scasagrande]

The cachability of k8s_test_setup, and thus tests that depend on it, has a dependency on your kubeconfig file. And since this contains certs, it will be different between each setup.

Normally this isn't a huge issue when a developer is locally re-running their tests, using their own local cache. However this causes cache issues for the following scenarios:

• in ci when using ephemeral runners (travis, etc), and you're setting up a local temporary k8s cluster (eg, kind). This will result in a new checksum every run, preventing you from being able to use cached test results
• developers using a centralized remote cache server
• developers adding content to their kubeconfig file will invalidate their test runs