iree/runtime/benchmark: fix: convert numpy.uint8 to ABI type i8

Signed-off-by: Florian Walbroel <walbroel@roofline.ai>

Author: Manewing

runtime/bindings/python/iree/runtime/benchmark.py

@@ -42,6 +42,7 @@
     numpy.dtype(numpy.int16): "i16",
     numpy.dtype(numpy.float16): "f16",
     numpy.dtype(numpy.int8): "i8",
+    numpy.dtype(numpy.uint8): "i8",
     numpy.dtype(numpy.bool_): "i1",
 }