The test java/net/httpclient/HttpsTunnelAuthTest.java calls proxy::stop when closing servers at the end of the test. The issue here is that ProxyServer doesn't define a `stop` method like other servers, but defines a `close` method.
However, because ProxyServer extends Thread, it does have an inherited deprecated `stop` method. But that's not what we want to call here.

The test diagnosability could also be improved by adding `trace` to the log categories.