fix(plugin-file-tree): add horizontal padding to comment style (#16)

Author: SoonIter

packages/rspress-plugin-file-tree/src/components/FileTree/FileTreeItem.module.less

@@ -53,6 +53,7 @@
 
 .comment {
   margin-left: 8px;
+  padding: 0 4px;
   color: var(--rp-c-text-2);
   font-style: italic;
   white-space: nowrap;