[IMP] core, bus: future werkzeug compatibility fixes

- `Response.charset` is deprecated since 2.3, `Response.set_cookie`
  accesses the currently-extent internal `_charset` directly until
  this too gets removed in Werkzeug 3.0. Add a `_charset` to
  `FutureResponse` so this does not crash.
- Bytes response headers are deprecated since 2.3, and will get
  removed in 3.0, passing bytes in websocket is completely unnecessary
  happenstance which is trivially fixed.

closes odoo/odoo#137145

X-original-commit: 66e3040d4ad9e03aabefebd4799f699ad30fca45
Signed-off-by: Julien Castiaux (juc) <juc@odoo.com>
Signed-off-by: Xavier Morel (xmo) <xmo@odoo.com>

addons/bus/websocket.py

@@ -862,7 +862,7 @@ class WebsocketConnectionHandler:
         return Response(status=101, headers={
             'Upgrade': 'websocket',
             'Connection': 'Upgrade',
-            'Sec-WebSocket-Accept': accept_header,
+            'Sec-WebSocket-Accept': accept_header.decode(),
         })
 
     @classmethod

odoo/http.py

@@ -1274,6 +1274,10 @@ class FutureResponse:
     def __init__(self):
         self.headers = werkzeug.datastructures.Headers()
 
+    @property
+    def _charset(self):
+        return self.charset
+
     @functools.wraps(werkzeug.Response.set_cookie)
     def set_cookie(self, key, value='', max_age=None, expires=-1, path='/', domain=None, secure=False, httponly=False, samesite=None, cookie_type='required'):
         if expires == -1:  # not forced value -> default value -> 1 year