fix generation generation

rebuild.sh

@@ -7,8 +7,7 @@ pushd ~/.nix
 git diff -U0 $(find . -name '*.nix')
 
 # add generation comment to flake.nix
-current_gen=$(nixos-rebuild list-generations | grep current | awk '{print $1}')
-gen=$((current_gen + 1))
+gen=$(nixos-rebuild list-generations | grep current | awk '{print $1}')
 if sed -n '3p' flake.nix | grep -q '^# generation:'; then
     # replace the comment on line 3
     sed -i "3s/^# generation:.*/# generation: $gen/" flake.nix