Add v1 api to e2e tests

[dsessler7]

Checklist:

• Have you added an explanation of what your changes do and why you'd like them to be included?
• Have you updated or added documentation for the change, as applicable?
• Have you tested your changes on all related environments with successful results, as applicable?
  • Have you added automated tests?

Type of Changes:

• New feature
• Bug fix
• Documentation
• Testing enhancement
• Other

What is the current behavior (link to any open issues here)?

Currently, the kuttl and chainsaw tests are hardcoded to use the v1beta1 postgrescluster API.

What is the new behavior (if this is a feature change)?

• Breaking change (fix or feature that would cause existing functionality to change)

Now, there are variables that can be used to set the postgrescluster API used by the kuttl and chainsaw tests. For kuttl, an environment variable, KUTTL_PGCLUSTER_API_VERSION, is set in the generate-kuttl make target. For chainsaw, versions.postgrescluster is set in the values.yaml file. The default for both is now v1.

There is also a commit to refactor an API CEL validation test.

Other Information: