jenkins: Include Deja-Vu fonts in system environment to silence jenkins warning.

(cherry picked from commit 241160aacc)

nixos/modules/services/continuous-integration/jenkins/default.nix

@@ -145,6 +145,11 @@ in {
   };
 
   config = mkIf cfg.enable {
+    # server references the dejavu fonts
+    environment.systemPackages = [
+      pkgs.dejavu_fonts
+    ];
+
     users.extraGroups = optional (cfg.group == "jenkins") {
       name = "jenkins";
       gid = config.ids.gids.jenkins;