Reduce setuptools requirement until [1] is resolved. Seems to work fine
with 63.x.

[1] https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=270358

--- pyproject.toml.orig	2024-04-20 11:55:50 UTC
+++ pyproject.toml
@@ -1,7 +1,7 @@
 # The project configuration for sip.
 
 [build-system]
-requires = ["setuptools>=64", "setuptools_scm>=8"]
+requires = ["setuptools>=63", "setuptools_scm>=8"]
 build-backend = "setuptools.build_meta"
 
 [tool.setuptools_scm]