Fix gather facts ignoring gather_subsets config (#59271)

* Fix gather facts ignoring gather_subsets config

 fixes #58728

* Update lib/ansible/playbook/play.py

Co-Authored-By: Abhijeet Kasurde <akasurde@redhat.com>

changelogs/fragments/gather_subset_defaults.yml

@@ -0,0 +1,2 @@
+bugfixes:
+    - Gather facts should use gather_subset config by default.

lib/ansible/playbook/play.py

@@ -57,7 +57,7 @@ class Play(Base, Taggable, CollectionSearch):
 
     # Facts
     _gather_facts = FieldAttribute(isa='bool', default=None, always_post_validate=True)
-    _gather_subset = FieldAttribute(isa='list', default=None, listof=string_types, always_post_validate=True)
+    _gather_subset = FieldAttribute(isa='list', default=(lambda: C.DEFAULT_GATHER_SUBSET), listof=string_types, always_post_validate=True)
     _gather_timeout = FieldAttribute(isa='int', default=C.DEFAULT_GATHER_TIMEOUT, always_post_validate=True)
     _fact_path = FieldAttribute(isa='string', default=C.DEFAULT_FACT_PATH)