Merge pull request #279174 from SuperSandro2000/iso-minimal-override

nixos/installation-cd-minimal: allow overwriting isoImage.edition with mkForce like other options

nixos/modules/installer/cd-dvd/installation-cd-minimal.nix

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   # not including it may cause annoying cache misses in the case of the NixOS manual.
   documentation.doc.enable = lib.mkOverride 500 true;
 
-  fonts.fontconfig.enable = lib.mkForce false;
+  fonts.fontconfig.enable = lib.mkOverride 500 false;
 
-  isoImage.edition = lib.mkForce "minimal";
+  isoImage.edition = lib.mkOverride 500 "minimal";
 }