updated guides to avoid connection: local (#44227)

- want they really need is `delegate_to: localhost`
 - also reduced 'local_action' usage in favor of same

docs/docsite/rst/dev_guide/developing_modules_general.rst

@@ -234,7 +234,6 @@ Ansible playbook.
 -  Add the following to the new playbook file::
 
     - name: test my new module
-      connection: local
       hosts: localhost
       tasks:
       - name: run the new module