setuptools: stable file ordering for sdist

We already re-pack the source distribution to make the
timestamps consistent, but the result is still not
entirely stable because by default tar does not sort
the files in the archive deterministically. This PR
makes sure the entries are sorted by name.

#105502

pkgs/development/python-modules/setuptools/default.nix

@@ -38,7 +38,7 @@ let
       # Here we untar the sdist and retar it in order to control the timestamps
       # of all the files included
       tar -xzf dist/${pname}-${version}.post0.tar.gz -C dist/
-      tar -czf dist/${name} -C dist/ --mtime="@$SOURCE_DATE_EPOCH"  ${pname}-${version}.post0
+      tar -czf dist/${name} -C dist/ --mtime="@$SOURCE_DATE_EPOCH" --sort=name ${pname}-${version}.post0
     '';
 
     installPhase = ''