pipeline: outputs: prometheus-remote-write: update docs with adding (#1057)

options related to aws sigv4 authentication

Signed-off-by: Clay Cheng <[email protected]>

Author: Claych

pipeline/outputs/prometheus-remote-write.md

@@ -13,6 +13,12 @@ Important Note: The prometheus exporter only works with metric plugins, such as
 | host                 | IP address or hostname of the target HTTP Server                                                                                                                                                                                                                       | 127.0.0.1 |
 | http_user            | Basic Auth Username                                                                                                                                                                                                                                                    |           |
 | http_passwd          | Basic Auth Password. Requires HTTP_user to be set                                                                                                                                                                                                                      |           |
+| AWS\_Auth                  | Enable AWS SigV4 authentication                                                                                                                                                                                                                                                                                                    | false     |
+| AWS\_Service               | For Amazon Managed Service for Prometheus, the service name is aps                                                                                                                   | aps          |
+| AWS\_Region                | Region of your Amazon Managed Service for Prometheus workspace                                                                                                                                                                                                                                                               |           |
+| AWS\_STS\_Endpoint         | Specify the custom sts endpoint to be used with STS API, used with the AWS_Role_ARN option, used by SigV4 authentication                                                                                                                                                                                                           |           |
+| AWS\_Role\_ARN             | AWS IAM Role to assume, used by SigV4 authentication                                                                                                                                                                                                                                                                               |           |
+| AWS\_External\_ID          | External ID for the AWS IAM Role specified with `aws_role_arn`, used by SigV4 authentication                                                                                                                                                                                                                                       |           |
 | port                 | TCP port of the target HTTP Server                                                                                                                                                                                                                                     | 80        |
 | proxy                | Specify an HTTP Proxy. The expected format of this value is `http://HOST:PORT`. Note that HTTPS is **not** currently supported. It is recommended not to set this and to configure the [HTTP proxy environment variables](https://docs.fluentbit.io/manual/administration/http-proxy) instead as they support both HTTP and HTTPS. |           |
 | uri                  | Specify an optional HTTP URI for the target web server, e.g: /something                                                                                                                                                                                                | /         |