Merge pull request 'upgrade nix in development to latest' (#1528) from nix-latest into main

checks/lib/container-test.nix

@@ -10,6 +10,7 @@ in
     hostPkgs = pkgs;
     # speed-up evaluation
     defaults = {
+      nix.package = pkgs.nixVersions.latest;
       documentation.enable = lib.mkDefault false;
       boot.isContainer = true;
 

checks/lib/test-base.nix

@@ -10,6 +10,7 @@ in
   defaults = {
     documentation.enable = lib.mkDefault false;
     nix.settings.min-free = 0;
+    nix.package = pkgs.nixVersions.latest;
   };
 
   # to accept external dependencies such as disko

devShell.nix

@@ -27,7 +27,8 @@
         packages = [
           select-shell
           pkgs.tea
-          pkgs.nix
+          # Better error messages than nix 2.18
+          pkgs.nixVersions.latest
           self'.packages.tea-create-pr
           self'.packages.merge-after-ci
           self'.packages.pending-reviews