modem: Remove ctx after deactivating it

Change-Id: Ib0e2a8ae8d9885fa44c9cc1f7dc7c7948abd683c
diff --git a/src/osmo_gsm_tester/modem.py b/src/osmo_gsm_tester/modem.py
index f0a0b24..5afd2d1 100644
--- a/src/osmo_gsm_tester/modem.py
+++ b/src/osmo_gsm_tester/modem.py
@@ -618,6 +618,9 @@
         ctx = systembus_get(ctx_id)
         ctx.SetProperty('Active', Variant('b', False))
         event_loop.wait(self, lambda: ctx.GetProperties()['Active'] == False)
+        self.dbg('deactivate_context active=false, removing', path=ctx_id)
+        connmgr = self.dbus.interface(I_CONNMGR)
+        connmgr.RemoveContext(ctx_id)
         self.log('context deactivated', path=ctx_id)
 
     def sms_send(self, to_msisdn_or_modem, *tokens):