replacing os.rpath with os.path.normpath()

suggested by codiumai-pr-agent-pro

Author: jkbzh

py/selenium/webdriver/firefox/webdriver.py

@@ -126,7 +126,7 @@ def install_addon(self, path, temporary=False) -> str:
         if os.path.isdir(path):
             fp = BytesIO()
             # filter all trailing slash found in path
-            path = path.rstrip(os.sep)
+            path = os.path.normpath(path)
             # account for trailing slash that will be added by os.walk()
             path_root = len(path) + 1
             with zipfile.ZipFile(fp, "w", zipfile.ZIP_DEFLATED) as zipped: