add changelog notes for breaking nomad changes

Author: cottand

nixos/doc/manual/release-notes/rl-2411.section.md

@@ -389,7 +389,9 @@
   before changing the package to `pkgs.stalwart-mail` in
   [`services.stalwart-mail.package`](#opt-services.stalwart-mail.package).
 
-- The `nomad_1_5` package was dropped, as [it has reached end-of-life upstream](https://support.hashicorp.com/hc/en-us/articles/360021185113-Support-Period-and-End-of-Life-EOL-Policy). Evaluating it will throw an error.
+- The `nomad_1_5` and `nomad_1_6` package were dropped, as [they have reached end-of-life upstream](https://support.hashicorp.com/hc/en-us/articles/360021185113-Support-Period-and-End-of-Life-EOL-Policy). Evaluating them will throw an error.
+
+- The default `nomad` package has been updated to 1.8.x. For more information, see [breaking changes for Nomad 1.8](https://developer.hashicorp.com/nomad/docs/upgrade/upgrade-specific#nomad-1-8-0)
 
 - `androidndkPkgs` has been updated to `androidndkPkgs_26`.