Implement e2e controller tests for the multi-version sample used in the docs

[camilamacedo86]

Description

See that we have the tutorial: https://book.kubebuilder.io/multiversion-tutorial/tutorial
All code used in this tutorial came from the sample in: https://github.com/kubernetes-sigs/kubebuilder/tree/master/docs/book/src/multiversion-tutorial/testdata/project

This sample is tested via the unit-test when we push a PR with changes.
Then, note that currently the EnvTest tests to test the reconciliation is commented:

https://github.com/kubernetes-sigs/kubebuilder/blob/master/docs/book/src/multiversion-tutorial/testdata/project/internal/controller/cronjob_controller_test.go#L87-L102

If we uncomment this line we will check in the CI/or when we run make tests for this project the following error:

"controllerGroup": "batch.tutorial.kubebuilder.io", "controllerKind": "CronJob", "CronJob": {"name":"test-resource","namespace":"default"}, "namespace": "default", "name": "test-resource", "reconcileID": "0504dde2-9a69-4126-829d-cd143fc79f8f", "active jobs": 0, "successful jobs": 0, "failed jobs": 0}
  2024-04-26T07:47:09Z	ERROR	unable to list child Jobs	{"error": "field label \".metadata.controller\" not supported for Job"}
  tutorial.kubebuilder.io/project/internal/controller.(*CronJobReconciler).Reconcile
  	/Users/runner/work/kubebuilder/kubebuilder/docs/book/src/multiversion-tutorial/testdata/project/internal/controller/cronjob_controller.go:132
  tutorial.kubebuilder.io/project/internal/controller.glob..func1.1.3
  	/Users/runner/work/kubebuilder/kubebuilder/docs/book/src/multiversion-tutorial/testdata/project/internal/controller/cronjob_controller_test.go:94
  github.com/onsi/ginkgo/v2/internal.extractBodyFunction.func3
  	/Users/runner/go/pkg/mod/github.com/onsi/ginkgo/v2@v2.14.0/internal/node.go:463
  github.com/onsi/ginkgo/v2/internal.(*Suite).runNode.func3
  	/Users/runner/go/pkg/mod/github.com/onsi/ginkgo/v2@v2.14.0/internal/suite.go:889

2024-04-26T07:47:09Z	DEBUG	job count	{"controller": "cronjob", "controllerGroup": "batch.tutorial.kubebuilder.io", "controllerKind": "CronJob", "CronJob": {"name":"test-resource","namespace":"default"}, "namespace": "default", "name": "test-resource", "reconcileID": "eb8800f5-c534-4025-a99e-0988b0d9321a", "active jobs": 0, "successful jobs": 0, "failed jobs": 0}
  [FAILED] in [It] - /Users/runner/work/kubebuilder/kubebuilder/docs/book/src/multiversion-tutorial/testdata/project/internal/controller/cronjob_controller_test.go:97 @ 04/26/24 07:47:09.663
  STEP: Cleaning up the specific resource instance of CronJob @ 04/26/24 07:47:09.663
  2024-04-26T07:47:09Z	DEBUG	no upcoming scheduled times, sleeping until next	{"controller": "cronjob", "controllerGroup": "batch.tutorial.kubebuilder.io", "controllerKind": "CronJob", "CronJob": {"name":"test-resource","namespace":"default"}, "namespace": "default", "name": "test-resource", "reconcileID": "eb8800f5-c534-4025-a99e-0988b0d9321a", "now": "2024-04-26T07:47:09Z", "next run": "2024-04-26T07:48:00Z"}
  << Timeline

  [FAILED] Unexpected error:
      <*errors.StatusError | 0x14000263b80>: 
      field label ".metadata.controller" not supported for Job
      {
          ErrStatus: {
              TypeMeta: {Kind: "", APIVersion: ""},
              ListMeta: {
                  SelfLink: "",
                  ResourceVersion: "",
                  Continue: "",
                  RemainingItemCount: nil,
              },
              Status: "Failure",
              Message: "field label \".metadata.controller\" not supported for Job",
              Reason: "BadRequest",
              Details: nil,
              Code: 400,
          },
      }
  occurred
  In [It] at: /Users/runner/work/kubebuilder/kubebuilder/docs/book/src/multiversion-tutorial/testdata/project/internal/controller/cronjob_controller_test.go:97 @\

Example: https://github.com/kubernetes-sigs/kubebuilder/actions/runs/8844368662/job/24286141139#step:5:474

What we need to do:

• Fix the reconcile implementation in: https://github.com/kubernetes-sigs/kubebuilder/blob/master/docs/book/src/multiversion-tutorial/testdata/project/internal/controller/cronjob_controller.go
• Ensure that we have tests to cover this implementation in: https://github.com/kubernetes-sigs/kubebuilder/blob/master/docs/book/src/multiversion-tutorial/testdata/project/internal/controller/cronjob_controller_test.go

Extra Labels

No response

[omerap12]

Maybe I can help with that
/assign