chore(flake.nix): fix shellcheck issues with luarocks installation code

Author: vhyrro

flake.nix

@@ -50,13 +50,13 @@
           nativeBuildInputs = with pkgs; [lua51Packages.luarocks wget];
           outputHashAlgo = "sha256";
           outputHashMode = "recursive";
-          outputHash = "sha256-dCr4RGzmOavixuO5kUg8SAwmi3bh1WX5cd0Nl+Vj26g=";
+          outputHash = "sha256-SOsIgtmkXTKMZrKUHHzAf+XAshl/J7+DN9RFeLz+DDY=";
         } ''
           mkdir $PWD/home
           export HOME=$PWD/home
           mkdir -p $out/luarocks
 
-          ${lib.concatStrings (lib.mapAttrsToList (name: version: "luarocks install --tree='$out/luarocks' --force-lock --local ${name} ${version}\n") dependencies)}
+          ${lib.concatStrings (lib.mapAttrsToList (name: version: ''luarocks install --tree="$out/luarocks" --force-lock --local ${name} ${version}'' + "\n") dependencies)}
         '';
         luarc = pkgs.mk-luarc {};
         luarc-with-dependencies =