Tests for private action runner helm chart

[dd-gplassard]

What this PR does / why we need it:

I initially wanted to do it in #1529 but I found out that my implementation

• was only making assertions on the service-account, all other resources were not checked. I believe this is due to the fact that common.Unmarshal(t, manifest, &actual) and common.LoadFromFile(t, baselineManifestPath, &baseline) actually only read the first entry from the yaml and ignores the following ones (not 100% sure about this but it matches my observation)
  

  helm-charts/test/private-action-runner/baseline_test.go

  Lines 67 to 81 in 8a47e13

  	func verifyPrivateActionRunner(t *testing.T, baselineManifestPath, manifest string) {
  	verifyBaseline(t, baselineManifestPath, manifest, appsv1.Deployment{}, appsv1.Deployment{})
  	verifyBaseline(t, baselineManifestPath, manifest, rbacv1.ClusterRole{}, rbacv1.ClusterRole{})
  	verifyBaseline(t, baselineManifestPath, manifest, rbacv1.RoleBinding{}, rbacv1.RoleBinding{})
  	verifyBaseline(t, baselineManifestPath, manifest, corev1.Secret{}, corev1.Secret{})
  	verifyBaseline(t, baselineManifestPath, manifest, corev1.Service{}, corev1.Service{})
  	verifyBaseline(t, baselineManifestPath, manifest, corev1.ServiceAccount{}, corev1.ServiceAccount{})
  	}
  	func verifyBaseline[T any](t *testing.T, baselineManifestPath, manifest string, baseline, actual T) {
  	common.Unmarshal(t, manifest, &actual)
  	common.LoadFromFile(t, baselineManifestPath, &baseline)
  	assert.True(t, cmp.Equal(baseline, actual, cmp.Options{}), cmp.Diff(baseline, actual))
  	}

  
  

  helm-charts/test/private-action-runner/baseline/Private_Action_Runner_default.yaml

  Lines 1 to 27 in 8a47e13

  	---
  	# Source: private-action-runner/templates/serviceaccount.yaml
  	apiVersion: v1
  	kind: ServiceAccount
  	metadata:
  	name: "private-action-runner-default-serviceaccount"
  	namespace: datadog-agent
  	---
  	# Source: private-action-runner/templates/secrets.yaml
  	apiVersion: v1
  	kind: Secret
  	metadata:
  	name: "private-action-runner-default-secrets"
  	namespace: datadog-agent
  	stringData:
  	config.yaml: |
  	ddBaseURL: https://app.datadoghq.com
  	urn: CHANGE_ME_URN_FROM_CONFIG
  	privateKey: CHANGE_ME_PRIVATE_KEY_FROM_CONFIG
  	modes:
  	- workflowAutomation
  	- appBuilder
  	port: 9016
  	actionsAllowlist:
  	- com.datadoghq.kubernetes.core.getPod
  	- com.datadoghq.kubernetes.core.listPod
  	---

• the tests were not running on the pull request because the only github workflow running unit test is restricted to test/datadog-operator/** and charts/datadog-operator/** paths

Special notes for your reviewer:

I'm not 100% sure of the best path forward about this.

• I went for using helm.DiffAgainstSnapshot which made bump a few dependencies.
• It also seems like tests from other packages are also not working so not sure what we should do about them.
• I more or less copy pasted the github workflow definition for datadog-operator, maybe there is a better solution ?