tests: python3 use byte strings in raw()

Raw('\xaf) and Raw(b'\xaf) are two quite different things in python 2 versus 3.
In most cases this didn't make a difference, apart from those cases where length
of payload actually mattered.

Type: fix
Signed-off-by: Ole Troan <ot@cisco.com>
Change-Id: I3cba5c1486e436a3ca8aa10a7b393da75aa9f6b9
diff --git a/src/plugins/flowprobe/test/test_flowprobe.py b/src/plugins/flowprobe/test/test_flowprobe.py
index 445ec6d..70b3acb 100644
--- a/src/plugins/flowprobe/test/test_flowprobe.py
+++ b/src/plugins/flowprobe/test/test_flowprobe.py
@@ -417,7 +417,7 @@
                             src=self.pg7.remote_mac) /
                       IP(src=self.pg7.remote_ip4, dst="9.0.0.100") /
                       TCP(sport=1234, dport=4321, flags=80) /
-                      Raw('\xa5' * 100))]
+                      Raw(b'\xa5' * 100))]
 
         nowUTC = int(time.time())
         nowUNIX = nowUTC+2208988800