test(components): update test for Switch.

Update its snapshot. It using `gap` rather than `margin` to set
elements' space. And remove useless `span` label if the label is
undefined.

Author: PeterlitsZo

packages/components/test/__snapshots__/index.js.snap

@@ -1649,6 +1649,7 @@ exports[`Switch renders 1`] = `
   display: -ms-flexbox;
   display: flex;
   cursor: pointer;
+  gap: 8px;
 }
 
 .emotion-1 {
@@ -1675,7 +1676,6 @@ exports[`Switch renders 1`] = `
   border-radius: 18px;
   height: 22px;
   width: 40px;
-  margin-right: 8px;
   padding: 2px;
 }
 
@@ -1738,7 +1738,6 @@ input:checked~.emotion-2>div {
       className="emotion-3"
     />
   </div>
-  <span />
 </label>
 `;