Fix asyncio tests: define resolution
diff --git a/Lib/asyncio/test_utils.py b/Lib/asyncio/test_utils.py
index ccb4454..42b9cd7 100644
--- a/Lib/asyncio/test_utils.py
+++ b/Lib/asyncio/test_utils.py
@@ -144,6 +144,10 @@
     def __init__(self):
         self.keys = {}
 
+    @property
+    def resolution(self):
+        return 1e-3
+
     def register(self, fileobj, events, data=None):
         key = selectors.SelectorKey(fileobj, 0, events, data)
         self.keys[fileobj] = key