Add a patch for restart-emacs

Before this change, trying to use `doom/restart-and-restore` would
result in a failed to load `default.el` as the wrong binary would be launched.

This fixes that.

default.nix

@@ -225,6 +225,7 @@ emacs.overrideAttrs (esuper:
       wrapEmacs() {
           wrapProgram $1 \
                     --set DOOMDIR ${doomDir} \
+                    --set NIX_DOOM_EMACS_BINARY $1 \
                     --set __DEBUG_doom_emacs_DIR ${doom-emacs} \
                     --set __DEBUG_doomLocal_DIR ${doomLocal}
       }