closeSocketFor does not destroy the web socket and causes memory leak

[sethphillips]

we tracked down a memory leak in our application that led us to sockets hanging around. turns out that the delete get(this, 'sockets')[cleanedUrl]; removes the reference but does not destroy the proxyObject. Getting that socket proxyObject and calling destroy() on it does remove it from memory though.
Happy to submit a PR if you need.

[cmackenz]

@sethphillips how are you destroying the proxyObject?

[sethphillips]

the proxyObject is returned from the socketFor method on the service.

@service websockets;
//...... random code
let socket = this.websockets.socketFor(someurl);
//...... random code 
socket.destroy()

[cmackenz]

@sethphillips thanks!