Add silent failing to kill on event loop errors

Add a try/catch to ensure silent fail on kill in case the event loop shuts down.

GH-4582

Author: srothh

sentry_sdk/transport.py

@@ -766,8 +766,10 @@ def kill(self: Self) -> None:
         for task in self.background_tasks:
             task.cancel()
         self.background_tasks.clear()
-
-        self._loop.create_task(self._pool.aclose())  # type: ignore
+        try:
+            self._loop.create_task(self._pool.aclose())  # type: ignore
+        except RuntimeError:
+            logger.warning("Event loop not running, aborting kill.")
 
 
 class HttpTransport(BaseHttpTransport):