fix(agw): Fixed integ test python syntx warning (magma#12996)

Signed-off-by: VinashakAnkitAman <ankit.aman@radisys.com>

lte/gateway/python/integ_tests/s1aptests/util/traffic_messages.py

@@ -146,7 +146,7 @@ def recv(stream):
         assert (not stream.closed) and stream.readable
 
         length = stream.readline()
-        if len(length) and length is not b'0':
+        if len(length) and length != b'0':
             length = int(length.decode())
             line = stream.read(length)
             return pickle.loads(line)