ggsn: Introduce test TC_pdp_act_restart_ctr_echo

VTY functionalities to enable and disable echo requests in osmo-ggsn are
added too as part of the test.

Depends: osmo-ggsn.git Id2c84165dc59dff495106758146a701ca488834f
Related: OS#4165
Change-Id: Ia37e48e7ff9ad063f9eabf447f8a6a0a3fc380d9
diff --git a/ggsn_tests/expected-results.xml b/ggsn_tests/expected-results.xml
index 374cde0..c31c14a 100644
--- a/ggsn_tests/expected-results.xml
+++ b/ggsn_tests/expected-results.xml
@@ -24,4 +24,5 @@
   <testcase classname='GGSN_Tests' name='TC_pdp46_act_deact_apn4' time='MASKED'/>
   <testcase classname='GGSN_Tests' name='TC_echo_req_resp' time='MASKED'/>
   <testcase classname='GGSN_Tests' name='TC_act_deact_retrans_duplicate' time='MASKED'/>
+  <testcase classname='GGSN_Tests' name='TC_pdp_act_restart_ctr_echo' time='MASKED'/>
 </testsuite>