Do not run window.history.replaceState unconditionally

Currently every Sphinx documentation page *always* drops `#:~:text=...` Text Fragments unconditionally due to `window.history.replaceState`.

The solution is to only call `window.history.replaceState` when a `?highlight=...` param is part of the URL.

Author: haampie

sphinx/themes/basic/static/sphinx_highlight.js

@@ -80,8 +80,10 @@ const SphinxHighlight = {
       || url.searchParams.get("highlight")
       || "";
     localStorage.removeItem("sphinx_highlight_terms");
-    url.searchParams.delete("highlight");
-    window.history.replaceState({}, "", url);
+    if (url.searchParams.has("highlight")) {
+      url.searchParams.delete("highlight");
+      window.history.replaceState({}, "", url);
+    }
 
     // get individual terms from highlight string
     const terms = highlight