fix(jobs): remove loop parameter from Semaphore in Python 3.8+ (#74)

The `loop` paramater of the `Semaphore` constructor is deprecated since
Python 3.8 and removed in 3.10.

rplugin/python3/ultest/vim_client/jobs/__init__.py

@@ -18,7 +18,6 @@ def __init__(self, num_threads: int = 2):
         self._jobs: defaultdict[str, Dict[str, Event]] = defaultdict(dict)
         self._loop = asyncio.new_event_loop()
         self._thread = Thread(target=self._loop.run_forever, daemon=True)
-        self._sem = Semaphore(num_threads, loop=self._loop)
         self._thread.start()
         if sys.version_info < (3, 8):
             # Use the new default watcher from  >= 3.8, implemented locally
@@ -27,6 +26,9 @@ def __init__(self, num_threads: int = 2):
 
             logger.info("Using local threaded child watcher")
             asyncio.set_child_watcher(ThreadedChildWatcher())
+            self._sem = Semaphore(num_threads, loop=self._loop)
+        else:
+            self._sem = Semaphore(num_threads)
 
     @property
     def semaphore(self) -> Semaphore: