removed YAML as documented local facts format as it is not supported and

would require extra modules on target.

docsite/rst/playbooks_variables.rst

@@ -671,7 +671,7 @@ For instance, what if you want users to be able to control some aspect about how
 .. note:: Perhaps "local facts" is a bit of a misnomer, it means "locally supplied user values" as opposed to "centrally supplied user values", or what facts are -- "locally dynamically determined values".
 
 If a remotely managed system has an "/etc/ansible/facts.d" directory, any files in this directory
-ending in ".fact", can be YAML, JSON, INI, or executable files returning JSON, and these can supply local facts in Ansible.
+ending in ".fact", can be JSON, INI, or executable files returning JSON, and these can supply local facts in Ansible.
 
 For instance assume a /etc/ansible/facts.d/preferences.fact::