Proposed title of this feature request

Allow Loki to send data to Object Storage using the VPC Endpoint provided by AWS, in alternative to the regular endpoint

Why does the customer need this? (List the business requirements)

This feature is required  because currently it is not supported to set up a VPC in AWS and, as things stands, Loki instances cannot flush logs from Openshift to S3 due to restriction of Loki to set only the regular endpoint as `aws_bucket_endpoint` parameter

List any affected packages or components.

Loki