Removes paramiko dependency from test-requires

Removing the paramiko dependency from tools/test-requires because it already
exists in tools/pip-requires. The tox.ini file includes both pip-requires and
test-requires and tox aborts because the dependency is essentially specified twice
(even though they do not have contradictory version requirements)

Change-Id: Ifc68f9ee52ed9b0dffc73c9cb710f611b3471051
diff --git a/tools/test-requires b/tools/test-requires
index fa98918..d3c7a1e 100644
--- a/tools/test-requires
+++ b/tools/test-requires
@@ -1,5 +1,4 @@
 pep8==1.3.3
 pylint==0.19
 # Needed for whitebox testing
-paramiko
 sqlalchemy