doc: update docs based on latest changes (#7)

Author: kldavis4

aws/terraform/modules/metaflow/modules/metadata-service/README.md

@@ -4,7 +4,6 @@ The Metadata Services exposes an API that our local computers interact with. Thi
 the Metadata Service to send to our Datastore for storage. Additionally, this is how we will request remote AWS
 Batch Jobs to be started as well as how we interrogate the Datastore for historical flow information.
 
-This implementation only accepts traffic originating from IP addresses defined by the variable
-`access_list_cidr_blocks`. Services internal to AWS can access the load balancer used by the API.
+If the `access_list_cidr_blocks` variable is set, only traffic originating from the specified IP addresses will be accepted. Services internal to AWS can directly access the load balancer used by the API.
 
 To read more, see [the Metaflow docs](https://docs.metaflow.org/metaflow-on-aws/metaflow-on-aws#metadata)