Update project to match expected operator-sdk v4 layout

[caseydavenport]

Description

The operator-sdk tool had stopped working a while back - we were still
on a v2 style project and the latest is v4!

I think this is a minimal set of changes to get the API generation
commands working - there might be additional work to get the full set of
operator-sdk functionality.

For PR author

• Tests for change.
• If changing pkg/apis/, run make gen-files
• If changing versions, run make gen-versions

For PR reviewers

A note for code reviewers - all pull requests must have the following:

• Milestone set according to targeted release.
• Appropriate labels:
  • kind/bug if this is a bugfix.
  • kind/enhancement if this is a a new feature.
  • enterprise if this PR applies to Calico Enterprise only.