nixos/promtheus-nextcloud-exporter: update module and test

Use new command-line flags of release 0.3.0 and always answer with the
expected XML in the VM test instead of using a test-specific fixed path.

Co-authored-by: ajs124 <git@ajs124.de>

nixos/modules/services/monitoring/prometheus/exporters/nextcloud.nix

@@ -46,11 +46,11 @@ in
       DynamicUser = false;
       ExecStart = ''
         ${pkgs.prometheus-nextcloud-exporter}/bin/nextcloud-exporter \
-          -a ${cfg.listenAddress}:${toString cfg.port} \
-          -u ${cfg.username} \
-          -t ${cfg.timeout} \
-          -l ${cfg.url} \
-          -p ${escapeShellArg "@${cfg.passwordFile}"} \
+          --addr ${cfg.listenAddress}:${toString cfg.port} \
+          --username ${cfg.username} \
+          --timeout ${cfg.timeout} \
+          --server ${cfg.url} \
+          --password ${escapeShellArg "@${cfg.passwordFile}"} \
           ${concatStringsSep " \\\n  " cfg.extraFlags}
       '';
     };

nixos/tests/prometheus-exporters.nix

@@ -423,7 +423,7 @@ let
       exporterConfig = {
         enable = true;
         passwordFile = "/var/nextcloud-pwfile";
-        url = "http://localhost/negative-space.xml";
+        url = "http://localhost";
       };
       metricProvider = {
         systemd.services.nc-pwfile = let
@@ -441,6 +441,7 @@ let
             basicAuth.nextcloud-exporter = "snakeoilpw";
             locations."/" = {
               root = "${pkgs.prometheus-nextcloud-exporter.src}/serverinfo/testdata";
+              tryFiles = "/negative-space.xml =404";
             };
           };
         };