fix nix flake check

Also adds a workaround for https://github.com/nix-community/home-manager/issues/2942

pkgs/python-pkgs/default.nix

@@ -1,4 +1,3 @@
 { callPackage }:
 {
-  recipemd = callPackage ./recipemd { };
 }

pkgs/python-pkgs/recipemd/default.nix

@@ -1,59 +0,0 @@
-{ lib
-, buildPythonPackage
-, fetchFromGitHub
-, pytestCheckHook
-, pythonPackages
-, installShellFiles
-, isPy36
-, isPy27
-}:
-
-buildPythonPackage rec {
-  pname = "recipemd";
-  version = "4.0.7";
-
-  disabled = isPy36 || isPy27;
-
-  src = fetchFromGitHub {
-    owner = "tstehr";
-    repo = "recipemd";
-    rev = "v4.0.7";
-    sha256 = "sha256-P65CxTaROfvx9kNSJWa5CiCUHCurTMZx8uUH9W9uK1U=";
-  };
-
-  propagatedBuildInputs = with pythonPackages; [
-    CommonMark
-    argcomplete
-    dataclasses-json
-    pyparsing
-    yarl
-  ];
-
-  nativeBuildInputs = [ installShellFiles ];
-
-  postInstall = ''
-    ${pythonPackages.argcomplete}/bin/register-python-argcomplete -s bash ${pname} > $out/completions.bash
-    installShellCompletion --bash --name recipemd.bash $out/completions.bash
-
-    ${pythonPackages.argcomplete}/bin/register-python-argcomplete -s fish ${pname} > $out/completions.fish
-    installShellCompletion --fish --name recipemd.fish $out/completions.fish
-
-    # The version of argcomplete in nixpkgs-stable does not have support for zsh
-    #${pythonPackages.argcomplete}/bin/register-python-argcomplete -s zsh ${pname} > $out/completions.zsh
-    #installShellCompletion --zsh --name _recipemd $out/completions.zsh
-  '';
-
-  checkInputs = [
-    pytestCheckHook
-    pythonPackages.pytestcov
-  ];
-
-  doCheck = true;
-
-  meta = with lib; {
-    description = "Markdown recipe manager, reference implementation of RecipeMD";
-    homepage = https://recipemd.org;
-    license = [ licenses.lgpl3Only ];
-    maintainers = [ maintainers.dadada ];
-  };
-}