[FIX] core/github_link: deprecated werkzeug method

Latest versions of werkzeug do not provide url_unparse anymore,
leading to an error during the build:

AttributeError: module 'werkzeug.urls' has no attribute 'url_unparse'

This commit replaces the use of url_unparse by the urllib counterpart.

closes odoo/documentation#12254

X-original-commit: b27431c271
Signed-off-by: Antoine Vandevenne (anv) <anv@odoo.com>
Signed-off-by: Victor Feyens (vfe) <vfe@odoo.com>

extensions/github_link/__init__.py

@@ -23,8 +23,8 @@ import importlib
 import inspect
 import os.path
 
-import werkzeug
 import contextlib
+from urllib.parse import urlunsplit
 
 
 def setup(app):
@@ -93,7 +93,7 @@ def make_github_link(app, project, path, line=None, mode="blob"):
         branch = 'master'
 
     urlpath = f"/{app.config.github_user}/{project}/{mode}/{branch}/{path}"
-    return werkzeug.urls.url_unparse((
+    return urlunsplit((
         'https',
         'github.com',
         urlpath,