msc: adjust routing-key to docker-playground's osmo-msc.cfg

Change-Id: I1fed051e933e7d9ee6da21b65b730b1b1846705a
diff --git a/msc/osmo-msc.cfg b/msc/osmo-msc.cfg
index 6db0cd3..61b146e 100644
--- a/msc/osmo-msc.cfg
+++ b/msc/osmo-msc.cfg
@@ -55,7 +55,7 @@
   remote-ip 127.0.0.1
  as as-clnt-OsmoMSC-A m3ua
   asp asp-clnt-OsmoMSC-A
-  routing-key 2 0.23.1
+  routing-key 3 0.23.1
 network
  network country code 262
  mobile network code 42