sgsn: fix RAU_ATTACH not to interact with following testes

TC_attach_rau will interact with the following tests, because the sgsn
is continuing sending RAU_ACCEPTs until it timed out or received a
RAU COMPLETE

Change-Id: Idac92bd61ee7145b7542e60c24e0a66b4ff7ddd4
diff --git a/sgsn/SGSN_Tests.ttcn b/sgsn/SGSN_Tests.ttcn
index adf87f2..0b439ec 100644
--- a/sgsn/SGSN_Tests.ttcn
+++ b/sgsn/SGSN_Tests.ttcn
@@ -753,6 +753,7 @@
 	alt {
 	[] BSSGP.receive(tr_BD_L3_MT(tr_GMM_RAU_ACCEPT)) -> value bd {
 		f_process_rau_accept(bd.l3_mt.msgs.gprs_mm.routingAreaUpdateAccept);
+		BSSGP.send(ts_GMM_RAU_COMPL);
 		setverdict(pass);
 		}
 	[] BSSGP.receive(tr_BD_L3_MT(tr_GMM_RAU_REJECT)) {