Update compileCloudWatchEventEvents.js

Possible fix for this issue #306 It allows to add already created role to CloudWatch event

Author: Taras Buchko

lib/deploy/events/cloudWatchEvent/compileCloudWatchEventEvents.js

@@ -73,7 +73,7 @@ module.exports = {
               .getStateMachineLogicalId(stateMachineName, stateMachineObj);
             const cloudWatchLogicalId = this
               .getCloudWatchEventLogicalId(stateMachineName, eventRuleNumberInFunction);
-            const cloudWatchIamRoleLogicalId = this
+            const cloudWatchIamRoleLogicalId = eventRule.iamRole || this
               .getCloudWatchEventToStepFunctionsIamRoleLogicalId(stateMachineName);
             const cloudWatchId = this.getCloudWatchEventId(stateMachineName);
             const policyName = this.getCloudWatchEventPolicyName(stateMachineName);