CLN: create asv input without overflow to prevent potential warnings

Author: SandroCasagrande

asv_bench/benchmarks/io/csv.py

@@ -287,7 +287,7 @@ def time_read_uint64_na_values(self):
 
 class ReadUint8Integers(StringIORewind):
     def setup(self):
-        arr = np.arange(10000).astype("uint8")
+        arr = np.tile(np.arange(256, dtype="uint8"), 500)
         self.data1 = StringIO("\n".join(arr.astype(str).tolist()))
 
     def time_read_uint8(self):