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/modules/cloud/amazon/lambda_facts.py

@@ -40,14 +40,10 @@ options:
   function_name:
     description:
       - The name of the lambda function for which facts are requested.
-    required: false
-    default: null
     aliases: [ "function", "name"]
   event_source_arn:
     description:
       - For query type 'mappings', this is the Amazon Resource Name (ARN) of the Amazon Kinesis or DynamoDB stream.
-    default: null
-    required: false
 author: Pierre Jodouin (@pjodouin)
 requirements:
     - boto3