net: update renamed test name in comment

TestSelfConnect from CL 5650071 was renamed TestTCPSelfConnect in CL 21447.

Change-Id: I0de110dbe1da77bfba540a1b51c139f3bedae67f
Reviewed-on: https://go-review.googlesource.com/c/go/+/213437Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>

src/net/dial_test.go

@@ -174,7 +174,7 @@ func dialClosedPort(t *testing.T) (actual, expected time.Duration) {
 	}
 	addr := l.Addr().String()
 	l.Close()
-	// On OpenBSD, interference from TestSelfConnect is mysteriously
+	// On OpenBSD, interference from TestTCPSelfConnect is mysteriously
 	// causing the first attempt to hang for a few seconds, so we throw
 	// away the first result and keep the second.
 	for i := 1; ; i++ {