Merge pull request #21524 from danbst/patch-8

Fix typo in iso-image.nix

nixos/modules/installer/cd-dvd/iso-image.nix

@@ -178,7 +178,7 @@ in
         image. It significantly increases image size. Use that when
         you want to be able to keep all the sources needed to build your
         system or when you are going to install the system on a computer
-        with slow on non-existent network connection.
+        with slow or non-existent network connection.
       '';
     };