refactor(tab): update nav padding

src/tabs/index.js

@@ -406,7 +406,7 @@ export default createComponent({
         <div
           ref="nav"
           role="tablist"
-          class={bem('nav', [type])}
+          class={bem('nav', [type, { complete: !ellipsis }])}
           style={this.navStyle}
         >
           {this.slots('nav-left')}

src/tabs/index.less

@@ -62,8 +62,6 @@
       }
 
       .van-tabs__nav {
-        padding-right: 8px;
-        padding-left: 8px;
         overflow-x: auto;
         overflow-y: hidden;
         -webkit-overflow-scrolling: touch;
@@ -71,6 +69,11 @@
         &::-webkit-scrollbar {
           display: none;
         }
+
+        &--complete {
+          padding-right: 8px;
+          padding-left: 8px;
+        }
       }
     }
   }