odoo17: fix longpoll server start

pkgs/by-name/od/odoo17/package.nix

@@ -55,6 +55,13 @@ python.pkgs.buildPythonApplication rec {
     }"
   ];
 
+  postPatch = ''
+    # hardcode the location of the unwrapped python scrip, otherwise the websocket
+    # server (called longpoll in codebase) will fail to start.
+    substituteInPlace odoo/service/server.py \
+      --replace-fail 'sys.argv[0]' "'${placeholder "out"}/bin/.odoo-wrapped'"
+  '';
+
   build-system = with python.pkgs; [
     setuptools
   ];