java/net/httpclient/AsyncShutdownNow.java fails intermittently

Waiting for HTTP operations to terminate...
gracedelay: 5000 ms, iterations: 500, wait/iteration: 10ms
WARNING: tracker for HttpClientImpl(4) has outstanding operations:
Pending HTTP Requests: 0
Pending HTTP/1.1 operations: 0
Pending HTTP/2 streams: 0
Pending WebSocket operations: 0
Pending TCP connections: 1
Pending Subscribers: 0
Total pending operations: 0
Facade referenced: false
Selector alive: false
Found 0 client still active, with 0 operations still pending out of 8 tracked clients.
AssertionError: Found some outstanding unclosed resources in 8 clients after 500 iterations and 14676 ms, waited 5000 ms