Remove legacy(?) intro point warning
PASS: mixed+hs-v23
Detail: chutney/tools/warnings.sh /Users/dev/tor/../chutney/tools/../net/nodes.1505199690
Warning: Established prop224 intro point on circuit 1041560573 Number: 1
Warning: Established prop224 intro point on circuit 1145630911 Number: 1
Warning: Established prop224 intro point on circuit 435989883 Number: 1