Enable AKS BYO nodepool test spec

[mboersma]

/kind cleanup

What needs cleanup:

The AKSBYONodeSpec was temporarily disabled in #5151, but should be restored when CAPZ reference image publishing catches up with AKS.

Describe the solution you'd like
[Description of how you would like the cleanup to be done.]

Files to change: 1

• test/e2e/azure_test.go
  • 856-866

Anything else you would like to add:
[Miscellaneous information that will assist in solving the issue.]

[nojnhuh]

This will involve reverting #5151 and its backports to release branches, so these three PRs in total:

• Skip AKS BYO nodepool test #5151
• [release-1.17] Skip AKS BYO nodepool test #5152
• [release-1.16] Skip AKS BYO nodepool test #5154