fix(stepfunctions-tasks): cluster creation fails with unresolved release labels (#18288)

Skipping validation in case the `props.releaseLabel` is unresolved.

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*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: otaviomacedo

packages/@aws-cdk/aws-stepfunctions-tasks/lib/emr/emr-create-cluster.ts

@@ -202,7 +202,7 @@ export class EmrCreateCluster extends sfn.TaskStateBase {
 
     this.taskPolicies = this.createPolicyStatements(this._serviceRole, this._clusterRole, this._autoScalingRole);
 
-    if (this.props.releaseLabel !== undefined) {
+    if (this.props.releaseLabel !== undefined && !cdk.Token.isUnresolved(this.props.releaseLabel)) {
       this.validateReleaseLabel(this.props.releaseLabel);
     }
 

packages/@aws-cdk/aws-stepfunctions-tasks/test/emr/emr-create-cluster.test.ts

@@ -34,6 +34,14 @@ beforeEach(() => {
   );
 });
 
+test('Create Cluster with an unresolved release label', () => {
+  new EmrCreateCluster(stack, 'Task', {
+    instances: {},
+    name: 'Cluster',
+    releaseLabel: cdk.Token.asString({}),
+  });
+});
+
 test('Create Cluster with FIRE_AND_FORGET integrationPattern', () => {
   // WHEN
   const task = new EmrCreateCluster(stack, 'Task', {