LibAudio: Clear callbacks and disconnect PulseAudioStream in destructor

If we don't clear the callbacks, they may be called after our functions
are deleted.

Disconnecting the stream also doesn't appear to be done automatically
when calling `pa_stream_unref()` for the last time, so let's do that.

Userland/Libraries/LibAudio/PulseAudioWrappers.cpp

@@ -266,11 +266,18 @@ ErrorOr<NonnullRefPtr<PulseAudioStream>> PulseAudioContext::create_stream(Output
         wait_for_signal();
     }
 
+    pa_stream_set_state_callback(stream, nullptr, nullptr);
+
     return stream_wrapper;
 }
 
 PulseAudioStream::~PulseAudioStream()
 {
+    auto locker = m_context->main_loop_locker();
+    pa_stream_set_write_callback(m_stream, nullptr, nullptr);
+    pa_stream_set_underflow_callback(m_stream, nullptr, nullptr);
+    pa_stream_set_started_callback(m_stream, nullptr, nullptr);
+    pa_stream_disconnect(m_stream);
     pa_stream_unref(m_stream);
 }