Add UPC temperature sensor monitoring

These sensors are part of their air quality measurements, which just
happen to be very close to our server room.

Reviewed-by: Aleix Boné <abonerib@bsc.es>

pkgs/upc-qaire-exporter/default.nix

@@ -0,0 +1,24 @@
+{ python3Packages, lib }:
+
+python3Packages.buildPythonApplication rec {
+  pname = "upc-qaire-exporter";
+  version = "1.0";
+
+  src = ./.;
+
+  doCheck = false;
+
+  build-system = with python3Packages; [
+    setuptools
+  ];
+
+  dependencies = with python3Packages; [
+    prometheus-client
+    requests
+  ];
+
+  meta = with lib; {
+    description = "UPC Qaire Prometheus Exporter";
+    platforms = platforms.linux;
+  };
+}