Align requirements

Change-Id: I744d1fa6aa2d5efa451fcefa4f859019c846bc67
diff --git a/tcp_tests/requirements.txt b/tcp_tests/requirements.txt
index a4149a8..8c30994 100644
--- a/tcp_tests/requirements.txt
+++ b/tcp_tests/requirements.txt
@@ -18,3 +18,4 @@
 salt-pepper
 setuptools<=36.2.0
 netaddr
+mock>=1.2