bpo-32089: Use default action for ResourceWarning (#4584)

In development and debug mode, use the "default" action, rather than
the "always" action, for ResourceWarning in the default warnings
filters.
diff --git a/Lib/warnings.py b/Lib/warnings.py
index 5b62569..c4bb22e 100644
--- a/Lib/warnings.py
+++ b/Lib/warnings.py
@@ -540,7 +540,7 @@
 
     # resource usage warnings are enabled by default in pydebug mode
     if dev_mode or py_debug:
-        resource_action = "always"
+        resource_action = "default"
     else:
         resource_action = "ignore"
     simplefilter(resource_action, category=ResourceWarning, append=1)