gdebugcontrollerdbus: Track pending tasks with weak refs
Rather than tracking them with a counter. This should close the race in
tracking the finalisation of the tasks by the task worker thread.
There’s no way to synchronise with that thread as it’s internal to
g_task_run_in_thread().
This should hopefully stop the debugcontroller test being flaky.
Signed-off-by: Philip Withnall pwithnall@endlessos.org