add doc entries for aws_endpoint_url_s3

Author: joelddiaz

doc/usage/al2.md

@@ -14,6 +14,7 @@
 | `arch` |  |
 | `associate_public_ip_address` |  |
 | `aws_access_key_id` |  |
+| `aws_endpoint_url_s3` | Use specified S3 endpoint for S3 calls (useful when running in non-commercial AWS environments).  |
 | `aws_region` |  |
 | `aws_secret_access_key` |  |
 | `aws_session_token` |  |

doc/usage/al2023.md

@@ -13,6 +13,7 @@
 | `arch` |  |
 | `associate_public_ip_address` |  |
 | `aws_access_key_id` |  |
+| `aws_endpoint_url_s3` | Use specified S3 endpoint for S3 calls (useful when running in non-commercial AWS environments).  |
 | `aws_region` |  |
 | `aws_secret_access_key` |  |
 | `aws_session_token` |  |