Fix flaky folder_watcher event entity test (#183686)

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Co-authored-by: Erwin Douna <e.douna@gmail.com>

tests/components/folder_watcher/test_event.py

@@ -1,11 +1,12 @@
 """The event entity tests for Folder Watcher."""
 
+import asyncio
 from pathlib import Path
-from time import sleep
 
 from syrupy.assertion import SnapshotAssertion
 
-from homeassistant.core import HomeAssistant
+from homeassistant.const import EVENT_STATE_CHANGED
+from homeassistant.core import Event, EventStateChangedData, HomeAssistant, callback
 from homeassistant.helpers import entity_registry as er
 from homeassistant.util import dt as dt_util
 
@@ -23,12 +24,24 @@ async def test_event_entity(
     entry = load_int
     await hass.async_block_till_done()
 
+    # Watchdog delivers events from its own threads, so wait for the final one.
+    moved = asyncio.Event()
+
+    @callback
+    def _async_state_changed(event: Event[EventStateChangedData]) -> None:
+        new_state = event.data["new_state"]
+        if new_state and new_state.attributes.get("event_type") == "moved":
+            moved.set()
+
+    hass.bus.async_listen(EVENT_STATE_CHANGED, _async_state_changed)
+
     file = tmp_path.joinpath("hello.txt")
     file.write_text("Hello, world!")
     new_file = tmp_path.joinpath("hello2.txt")
     file.rename(new_file)
 
-    await hass.async_add_executor_job(sleep, 0.1)
+    async with asyncio.timeout(10):
+        await moved.wait()
 
     entity_entries = er.async_entries_for_config_entry(entity_registry, entry.entry_id)
     assert entity_entries