Switch from Force Tags to Test Tags

Force Tags is deprecated in Robot 7.0 and will eventually
warn and then after that stop working. Test Tags performs
the same function per docs.

Change-Id: I7cf305754b247b995a05d8da3b9de9ed613ecae2
Signed-off-by: Matt Fischer <matthew.fischer@hpe.com>
diff --git a/network/test_vlan_network.robot b/network/test_vlan_network.robot
index 8feb2fb..1b6a4c8 100644
--- a/network/test_vlan_network.robot
+++ b/network/test_vlan_network.robot
@@ -18,7 +18,7 @@
 
 Suite Teardown                  Suite Teardown Execution
 
-Force Tags                      VLAN_Network
+Test Tags                      VLAN_Network
 
 *** Variables ***