tests: use connection-monitor and verify results

Test 1008 and 206 don't show the disconnect since it happens when SWS
awaits a new request, but 503 does and so the verify section needs that
string added.

tests/data/test206

@@ -12,6 +12,9 @@ HTTP proxy Digest auth
 
 # Server-side
 <reply>
+<servercmd>
+connection-monitor
+</servercmd>
 
 # this is returned first since we get no proxy-auth
 <data>