Fix numpy upgrade to 2.0.0 BUFSIZE import error (#5680)

Numpy 2.0.0 removed the BUFSIZE API, replacing it with
'numpy._core.umath.BUFSIZE'.

The minimum numpy version supported by the new code is 1.26.1. If you
need to support the lower numpy version, please tell me and we can add
another path.

Co-authored-by: Logan Adams <114770087+loadams@users.noreply.github.com>

deepspeed/autotuning/scheduler.py

@@ -5,7 +5,11 @@
 
 import copy
 
-from numpy import BUFSIZE
+import numpy
+if numpy.__version__ < '2.0.0':
+    from numpy import BUFSIZE
+else:
+    from numpy._core.umath import BUFSIZE
 import json
 import subprocess
 import sys