python: Fix protobuf supported range

note: using python 5.28 will lead to multiple segfault

Author: Mizux

ortools/python/setup.py.in

@@ -46,7 +46,7 @@ setup(
         'absl-py >= 2.0.0',
         'numpy >= 1.13.3',
         'pandas >= 2.0.0',
-        'protobuf >= 5.26.1',
+        'protobuf >= 5.26.1,<5.27',
         'immutabledict >= 3.0.0',
     ],
     package_data={