host/tatos: add nginx exporters to the prometheus

hosts/tatos/services/prometheus.nix

@@ -2,6 +2,7 @@
 
 let
   nodeExporterPort = 40000;
+  nginxExporterPort = 40001;
 in
 {
   services.prometheus.exporters.node = {
@@ -45,6 +46,17 @@ in
           }
         ];
       }
+      {
+        job_name = "nginx_production";
+        static_configs = [
+          {
+            targets = [
+              "canigou:${toString nginxExporterPort}"
+              "magenta:${toString nginxExporterPort}"
+            ];
+          }
+        ];
+      }
     ];
   };
 }