Ensure ConditionCheck container names are DNS-safe.

My recent change uncovered a latent bug where especially long test names result in especially long container names, which fails certain validations.  Unfortunately it slipped in because the test was expected to fail.

This leverages the names.SimpleNameGenerator.RestrictLength helper to solve this problem.

Fixes: #3393

pkg/reconciler/pipelinerun/resources/conditionresolution.go

@@ -25,6 +25,7 @@ import (
 	"github.com/tektoncd/pipeline/pkg/apis/pipeline/v1beta1"
 	"github.com/tektoncd/pipeline/pkg/apis/resource"
 	resourcev1alpha1 "github.com/tektoncd/pipeline/pkg/apis/resource/v1alpha1"
+	"github.com/tektoncd/pipeline/pkg/names"
 	corev1 "k8s.io/api/core/v1"
 )
 
@@ -96,7 +97,7 @@ func (state TaskConditionCheckState) IsSuccess() bool {
 // ConditionToTaskSpec creates a TaskSpec from a given Condition
 func (rcc *ResolvedConditionCheck) ConditionToTaskSpec() (*v1beta1.TaskSpec, error) {
 	if rcc.Condition.Spec.Check.Name == "" {
-		rcc.Condition.Spec.Check.Name = unnamedCheckNamePrefix + rcc.Condition.Name
+		rcc.Condition.Spec.Check.Name = names.SimpleNameGenerator.RestrictLength(unnamedCheckNamePrefix + rcc.Condition.Name)
 	}
 
 	t := &v1beta1.TaskSpec{

pkg/reconciler/pipelinerun/resources/conditionresolution_test.go

@@ -215,6 +215,18 @@ func TestResolvedConditionCheck_ConditionToTaskSpec(t *testing.T) {
 				Image: "ubuntu",
 			}}},
 		},
+	}, {
+		name: "default-container-name",
+		cond: tbv1alpha1.Condition("very-very-very-very-very-very-very-very-very-very-very-long-name", tbv1alpha1.ConditionSpec(
+			tbv1alpha1.ConditionSpecCheck("", "ubuntu"),
+		)),
+		want: v1beta1.TaskSpec{
+			Steps: []v1beta1.Step{{Container: corev1.Container{
+				// Shortened via: names.SimpleNameGenerator.RestrictLength
+				Name:  "condition-check-very-very-very-very-very-very-very-very-very-ve",
+				Image: "ubuntu",
+			}}},
+		},
 	}, {
 		name: "with-input-params",
 		cond: tbv1alpha1.Condition("bar", tbv1alpha1.ConditionSpec(