python3Packages.sqlalchemy_1_4: drop tag_build to fix version

copied from python3Packages.sqlalchemy

> https://hydra.nixos.org/build/246233876/nixlog/1
> sqlalchemy<1.5,>=1.3.0 not satisfied by version 1.4.51.dev0

pkgs/development/python-modules/sqlalchemy/1_4.nix

@@ -45,6 +45,10 @@ buildPythonPackage rec {
     hash = "sha256-KhLSKlQ4xfSh1nsAt+cRO+adh2aj/h/iqV6YmDbz39k=";
   };
 
+  postPatch = ''
+    sed -i '/tag_build = dev/d' setup.cfg
+  '';
+
   nativeBuildInputs = [
     setuptools
   ];