Fix build with Cython 3

This upstream commit should be included with 1.8.3.

cython3.patch

@@ -0,0 +1,14 @@
+Backport of https://github.com/pythongssapi/python-gssapi/pull/321
+
+diff --git a/gssapi/raw/_enum_extensions/ext_dce.pyx b/gssapi/raw/_enum_extensions/ext_dce.pyx
+index fd2989ae..190c8285 100644
+--- a/gssapi/raw/_enum_extensions/ext_dce.pyx
++++ b/gssapi/raw/_enum_extensions/ext_dce.pyx
+@@ -1,6 +1,6 @@
+ from gssapi.raw.cython_types cimport OM_uint32
+ 
+-import gssapi.raw._enum_extensions as ext_registry
++from gssapi.raw import _enum_extensions as ext_registry
+ 
+ 
+ cdef extern from "python_gssapi_ext.h":

python-gssapi.spec

@@ -8,6 +8,8 @@ Summary:        Python Bindings for GSSAPI (RFC 2743/2744 and extensions)
 License:        ISC
 URL:            https://github.com/pythongssapi/python-gssapi
 Source0:        https://github.com/pythongssapi/%{name}/releases/download/v%{version}/%{name}-%{version}.tar.gz
+# https://github.com/pythongssapi/python-gssapi/pull/321
+Patch0:         cython3.patch
 
 BuildRequires:  krb5-devel >= 1.19
 BuildRequires:  gcc