ha-mqtt-discoverable-cli: pin paho-mqtt to v1

pkgs/by-name/ha/ha-mqtt-discoverable-cli/package.nix

···
   python3,
 }:
 
-python3.pkgs.buildPythonApplication rec {
+let
+  python = python3.override {
+    self = python;
+    packageOverrides = self: super: {
+      # https://github.com/unixorn/ha-mqtt-discoverable/pull/310
+      paho-mqtt = self.paho-mqtt_1;
+    };
+  };
+in
+python.pkgs.buildPythonApplication rec {
   pname = "ha-mqtt-discoverable-cli";
   version = "0.16.4.1";
   pyproject = true;
···
 
   pythonRelaxDeps = [ "ha-mqtt-discoverable" ];
 
-  build-system = with python3.pkgs; [ poetry-core ];
+  build-system = with python.pkgs; [ poetry-core ];
 
-  dependencies = with python3.pkgs; [ ha-mqtt-discoverable ];
+  dependencies = with python.pkgs; [ ha-mqtt-discoverable ];
 
   # Project has no real tests
   doCheck = false;