docs: warn against using s3.amazonaws.com as endpoint-url

Add warning to S3 configuration docs advising against using the global
S3 endpoint (s3.amazonaws.com) as --endpoint-url parameter value to
prevent PermanentRedirect errors and other unwanted behaviors/errors from S3

Addresses aws#9479

Author: adev-code

awscli/topics/s3-config.rst

@@ -18,7 +18,7 @@ for performance reasons or to account for the specific environment where these
 .. warning::
    S3 commands have a parameter ``--endpoint-url`` that overrides the command's
    default URL with the given URL. Avoid using the S3 Global Endpoint
-   (s3.amazonaws.com) as the value for this parameter to prevent redirect
+   (``https://s3.amazonaws.com``) as the value for this parameter to prevent redirect
    issues and other unintended behavior or errors from S3.
 
 Configuration Values