docsp-27037 - AWS EKS Auth (#346)

* add auth

* db feedback

Author: mongoKart

source/fundamentals/auth.txt

@@ -390,6 +390,7 @@ The next examples show how to provide your credentials by setting environment
 variables for the following types of authentication:
 
 - Programmatic access keys
+- Web identity provider
 - ECS container credentials
 - EC2 container credentials
 
@@ -405,6 +406,23 @@ in environment variables by using ``bash`` or a similar shell:
 Omit the line containing ``AWS_SESSION_TOKEN`` if you don't need an AWS
 session token for that role.
 
+You can use an OpenID Connect (OIDC)-compatible **web identity provider** to authenticate
+to Amazon Elastic Kubernetes Service (EKS) or other services.
+
+.. important::
+
+   Your project must include v1 or v2 of the AWS SDK as a dependency to authenticate 
+   using a web identity provider.
+
+To use a web identity provider, create a file that contains your
+OIDC token. Next, use ``bash`` or a similar shell to set an environment variable
+to the absolute path to this file, as shown in the following example:
+
+.. code-block:: bash
+
+   export AWS_WEB_IDENTITY_TOKEN_FILE=<absolute path to file containing your OIDC token>
+
+
 To authenticate by using **ECS container credentials**, set the ECS
 endpoint relative URI in an environment variable by using ``bash`` or
 a similar shell as shown in the following example: