fix(list): fix padding for list items

Author: kara

src/lib/list/list.scss

@@ -80,7 +80,7 @@ $mat-dense-list-icon-size: 20px;
     @include mat-line-wrapper-base();
     padding: 0 $mat-list-side-padding;
 
-    &:first-child {
+    &:nth-child(2) {
       padding: 0;
     }
   }