nixos/jenkins: Drop default packages from package option

Not every Jenkins installation needs any package included in PATH. Drop
the packages from `services.jenkins.packages` and leave the decision up
to the user instead.

Add a release note to 26.05 in order to notify users.

Signed-off-by: Felix Singer <felixsinger@posteo.net>

doc/release-notes/rl-2605.section.md

@@ -221,6 +221,8 @@
 
 - `services.taskchampion-sync-server` module have been added an option `services.taskchampion-sync-server.dynamicUser` to use systemd's DynamicUser feature. This is enabled by default when stateVersion is at least 26.05, and disabled otherwise. If you need this feature, you need to set `services.taskchampion-sync-server.dynamicUser` to `true` and migrate `/var/lib/taskchampion-sync-server` to `/var/lib/private/taskchampion-sync-server`.
 
+- The default packages in `services.jenkins.packages` have been dropped, since not every Jenkins installation needs any package at all. It's more reasonable to leave it empty and let users configure what they need.
+
 ## Other Notable Changes {#sec-nixpkgs-release-26.05-notable-changes}
 
 <!-- To avoid merge conflicts, consider adding your item at an arbitrary place in the list instead. -->

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

@@ -86,14 +86,16 @@ in
       javaPackage = lib.mkPackageOption pkgs "jdk25" { };
 
       packages = lib.mkOption {
-        default = [
-          pkgs.stdenv
-          pkgs.git
-          pkgs.jdk25
-          config.programs.ssh.package
-          pkgs.nix
-        ];
-        defaultText = lib.literalExpression "[ pkgs.stdenv pkgs.git pkgs.jdk17 config.programs.ssh.package pkgs.nix ]";
+        default = [ ];
+        example = lib.literalExpression ''
+          [
+            pkgs.stdenv
+            pkgs.git
+            pkgs.jdk25
+            config.programs.ssh.package
+            pkgs.nix
+          ]
+        '';
         type = lib.types.listOf lib.types.package;
         description = ''
           Packages to add to PATH for the jenkins process.