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/ec2_vpc_nat_gateway.py

@@ -23,33 +23,25 @@ options:
   state:
     description:
       - Ensure NAT Gateway is present or absent.
-    required: false
     default: "present"
     choices: ["present", "absent"]
   nat_gateway_id:
     description:
       - The id AWS dynamically allocates to the NAT Gateway on creation.
         This is required when the absent option is present.
-    required: false
-    default: None
   subnet_id:
     description:
       - The id of the subnet to create the NAT Gateway in. This is required
         with the present option.
-    required: false
-    default: None
   allocation_id:
     description:
       - The id of the elastic IP allocation. If this is not passed and the
         eip_address is not passed. An EIP is generated for this NAT Gateway.
-    required: false
-    default: None
   eip_address:
     description:
       - The elastic IP address of the EIP you want attached to this NAT Gateway.
         If this is not passed and the allocation_id is not passed,
         an EIP is generated for this NAT Gateway.
-    required: false
   if_exist_do_not_create:
     description:
       - if a NAT Gateway exists already in the subnet_id, then do not create a new one.
@@ -60,25 +52,20 @@ options:
       - Deallocate the EIP from the VPC.
       - Option is only valid with the absent state.
       - You should use this with the wait option. Since you can not release an address while a delete operation is happening.
-    required: false
-    default: true
+    default: 'yes'
   wait:
     description:
       - Wait for operation to complete before returning.
-    required: false
-    default: false
+    default: 'no'
   wait_timeout:
     description:
       - How many seconds to wait for an operation to complete before timing out.
-    required: false
     default: 300
   client_token:
     description:
       - Optional unique token to be used during create to ensure idempotency.
         When specifying this option, ensure you specify the eip_address parameter
         as well otherwise any subsequent runs will fail.
-    required: false
-
 author:
   - "Allen Sanabria (@linuxdynasty)"
   - "Jon Hadfield (@jonhadfield)"