Merge pull request #210930 from pennae/installer-test-no-docs

nixosTests.installer.*: disable documentation

nixos/tests/installer.nix

···
             <nixpkgs/nixos/modules/testing/test-instrumentation.nix>
           ];
 
+        documentation.enable = false;
+
         # To ensure that we can rebuild the grub configuration on the nixos-rebuild
         system.extraDependencies = with pkgs; [ stdenvNoCC ];