event > workflow ..added default blank option to workflow dropdown

packages/builder/src/components/userInterface/EventsEditor/StateBindingCascader.svelte

@@ -25,6 +25,7 @@
   {/if}
   {#if parameter.name === 'workflow'}
     <Select on:change bind:value={parameter.value}>
+      <option value=""></option>
       {#each $workflowStore.workflows.filter(wf => wf.live) as workflow}
         <option value={workflow._id}>{workflow.name}</option>
       {/each}