treewide: add explicit format attribute for Python packages

If a Python package does not come with either `format` or `pyproject` we
consider it a setuptools build, that calls `setup.py` directly, which is
deprecated.

This change, as a first step, migrates a large chunk of these packages to
set setuptools as their explicit format

This is so we can unify the problem space for the next step of the
migration.

pkgs/development/interpreters/python/tests/test_nix_pythonprefix/typeddep/default.nix

@@ -8,6 +8,7 @@ buildPythonPackage {
 
   pname = "typeddep";
   version = "1.3.3.7";
+  format = "setuptools";
 
   src = lib.fileset.toSource {
     root = ./.;