Rename env to gems in default.nix

default.nix

@@ -1,7 +1,7 @@
 { bundlerEnv, ruby, stdenv }:
 
 let
-  env = bundlerEnv {
+  gems = bundlerEnv {
     inherit ruby;
 
     name = "render-test";
@@ -13,14 +13,14 @@ in
   stdenv.mkDerivation {
     name = "katex-converter";
     src = ./convert.rb;
-    buildInputs = [ env ruby ];
+    buildInputs = [ gems ruby ];
     unpackPhase = "echo 'Skipping unpack phase (nothing to unpack)'";
     installPhase = ''
       mkdir -p $out/{bin,share/katex-converter}
       cp $src $out/share/katex-converter/convert.rb
 	cat > $out/bin/katex-converter <<EOF
 #!/bin/sh -e
-exec ${env}/bin/bundle exec ${ruby}/bin/ruby $out/share/katex-converter/convert.rb \$@
+exec ${gems}/bin/bundle exec ${ruby}/bin/ruby $out/share/katex-converter/convert.rb \$@
 EOF
       chmod +x $out/bin/katex-converter
     '';