Addressed review comments

Author: Tarun Belani

packages/@aws-cdk/aws-imagebuilder-alpha/lib/workflow.ts

@@ -145,7 +145,7 @@ export interface WorkflowAttributes {
 
   /**
    * The version of the workflow
-   * - x.x.x
+   *
    * @default x.x.x
    */
   readonly workflowVersion?: string;