refactor: remove useless div tag

src/UIShell/GlobalHeader/HeaderAction.svelte

@@ -54,8 +54,7 @@
   }}"
 />
 
-<div>
-  <button
+<button
   bind:this="{ref}"
   type="button"
   class:bx--header__action="{true}"
@@ -67,7 +66,7 @@
     isOpen = !isOpen;
     dispatch(isOpen ? 'open' : 'close');
   }}"
-  >
+>
   <svelte:component this="{icon}" style="{isOpen ? 'display: none' : ''}" />
   <svelte:component
     this="{closeIcon}"
@@ -76,8 +75,8 @@
   <slot name="text">
     {#if text}<span>{text}</span>{/if}
   </slot>
-  </button>
-  {#if isOpen}
+</button>
+{#if isOpen}
   <div
     bind:this="{refPanel}"
     class:bx--header-panel="{true}"
@@ -89,8 +88,7 @@
   >
     <slot />
   </div>
-  {/if}
-</div>
+{/if}
 
 <style>
   .action-text {