Remove +1 when calculating news url prefix

Author: nginx-jack

source/exts/nxt.py

@@ -673,7 +673,7 @@ def run(self) -> List[Node]:
         self.items.append(self.options)
         node = nxt_news_entry()
         node.options = self.options
-        node.prefix = "../" * (env.docname.count("/") + 1)
+        node.prefix = "../" * (env.docname.count("/"))
         self.options["anchor"] = (
             env.docname.rsplit("/", 1)[0]
             + "/#"