[numpy] Fix users of NumPy APIs that are removed in NumPy 2.0.

This change migrates users of APIs removed in NumPy 2.0 to their recommended replacements (https://numpy.org/devdocs/numpy_2_0_migration_guide.html).

PiperOrigin-RevId: 656080533

tensorflow_gnn/converters/ogb/ogb_lib.py

@@ -44,7 +44,7 @@ def generate_examples(features: DataTable,
         value = feat.float_list.value
       elif array.dtype.type in (numpy.bytes_,):
         value = feat.bytes_list.value
-      elif array.dtype.type in (numpy.string_, numpy.str_):
+      elif array.dtype.type in (numpy.bytes_, numpy.str_):
         value = [word.encode("utf-8") for word in feat.bytes_list.value]
       else:
         raise NotImplementedError(