docs: update copy related to null-label variables

Author: sgtoj

README.md

@@ -31,14 +31,13 @@ module "cognito_custom_sms_sender" {
 }
 ```
 
-## Requirements
-
-- Terraform 0.13.0 or later
-- AWS provider 5.0.0 or later
-- Docker installed and running on the machine where Terraform is executed
-
 ## Inputs
 
+In addition to the variables documented below, this module includes several
+other optional variables (e.g., `name`, `tags`, etc.) provided by the
+`cloudposse/label/null` module. Please refer to its [documentation](https://registry.terraform.io/modules/cloudposse/label/null/latest)
+for more details on these variables.
+
 | Name                                    | Description                                                                                                                                                                  |   Type   |  Default  | Required |
 |-----------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|:--------:|:---------:|:--------:|
 | `kms_key_alias_prefix`                  | The prefix for the KMS key alias. It must start with 'alias' and only include alphanumeric characters, dashes, underscores, colons or slashes, but doesn't end with a slash. | `string` | `"alias"` |    no    |
@@ -49,13 +48,6 @@ module "cognito_custom_sms_sender" {
 | `aws_account_id`                        | The AWS account ID that the module will be deployed in.                                                                                                                      | `string` |   `""`    |    no    |
 | `aws_region_name`                       | The AWS region name where the module will be deployed.                                                                                                                       | `string` |   `""`    |    no    |
 
-### Note
-
-This module uses the `cloudposse/label/null` module for naming and tagging
-resources. As such, it also includes a `context.tf` file with additional
-optional variables you can set. Refer to the [`cloudposse/label` documentation](https://registry.terraform.io/modules/cloudposse/label/null/latest)
-for more details on these variables.
-
 ## Outputs
 
 | Name            | Description                                                        |