[3.11] gh-108416: Mark slow test methods with @requires_resource('cpu') (GH-108421) (GH-108799)

Only mark tests which spend significant system or user time,
by itself or in subprocesses.
(cherry picked from commit f3ba0a74cd)

Lib/test/test_exceptions.py

@@ -1304,6 +1304,7 @@ def g():
 
 
     @cpython_only
+    @support.requires_resource('cpu')
     def test_trashcan_recursion(self):
         # See bpo-33930