wasip3: Closing a socket resource does not always close the socket #11342
Description
Currently there is liberal use of Arc<...> in the WASIp3 wasi:sockets implementation which is used for sharing sockets between tasks which are used to implement streams. One example is that a stream of clients can be extracted from a TCP listener, meaning that the underlying socket is now shared between the original TCP listener resource and the stream that is reading clients. The consequence of this implementation is that when the resource is closed it does not mean that the actual socket is itself closed. For example the OS-level port remains reserved until the task for accepted clients also exits. While the tasks will "promptly exit" there is currently no reliable mechanism to await this happening.
This leads to tests for REUSEADDR, for example, having a loop around re-binding a port and asserting it's successful. This test is being added in #11291.