uasyncio: benchmark/boom_uasyncio.py: More assert output.

Author: pfalcon

uasyncio/benchmark/boom_uasyncio.py

@@ -19,7 +19,7 @@ def validate(resp):
  no = int(l.split()[1])
  seen.append(no)
  c = t.count(l + "\r\n")
- assert c == 400101
+ assert c == 400101, str(c)
  assert t.endswith("=== END ===")
 
  cnt += 1