Clean up module documentation (#36909)

* Clean up module documentation

This PR includes:
- Removal of `default: None` (and variations)
- Removal of `required: false`
- Fixing booleans and `type: bool` where required

* Fix remaining (new) validation issues

lib/ansible/utils/module_docs_fragments/a10.py

@@ -28,35 +28,30 @@ options:
     description:
       - Hostname or IP of the A10 Networks device.
     required: true
-    default: null
   username:
     description:
       - An account with administrator privileges.
     required: true
     aliases: ['user', 'admin']
-    default: null
   password:
     description:
       - Password for the C(username) account.
     required: true
     aliases: ['pass', 'pwd']
-    default: null
   write_config:
     description:
       - If C(yes), any changes will cause a write of the running configuration
         to non-volatile memory. This will save I(all) configuration changes,
         including those that may have been made manually or through other modules,
         so care should be taken when specifying C(yes).
-    required: false
     version_added: 2.2
-    default: "no"
-    choices: ["yes", "no"]
+    type: bool
+    default: 'no'
   validate_certs:
     description:
       - If C(no), SSL certificates will not be validated. This should only be used
         on personally controlled devices using self-signed certificates.
-    required: false
     version_added: 2.2
+    type: bool
     default: 'yes'
-    choices: ['yes', 'no']
 """