Remove redundant comment

static/css/elegant.less

@@ -138,7 +138,7 @@ body {
 footer {
     align-items: center;
     background-color: @el-page-footer-color;
-    border-top: @el-page-footer-border-top;//1px solid  rgba(0, 0, 0, .2);
+    border-top: @el-page-footer-border-top;
     bottom: 0;
     display: flex;
     height: @el-page-footer-height;