Allow support for aws service endpoint env vars with aws-sdk-v2

[matthewhudsonedb]

AWS has introduced service endpoint env vars

This allows for setting the following env vars when using aws-sdk-v2:

AWS_ENDPOINT_URL_
Specifies a custom endpoint that is used for a specific service, where is replaced with the AWS service identifier. For example, Amazon DynamoDB has a serviceId of DynamoDB. For this service, the endpoint URL environment variable is AWS_ENDPOINT_URL_DYNAMODB.

For a list of all service-specific environment variables, see List of service-specific identifiers.

Setting the following ENV VARS with aws-sdk-v2 enabled should allow thanos to connect to the respective services:
AWS_ENDPOINT_URL_S3: https://minio.minio-tenant-default.svc.cluster.local:443
AWS_ENDPOINT_URL_STS: https://sts.minio-operator.svc.cluster.local:4223/sts/minio-tenant-default

[matthewhudsonedb]

I have the following PR which bumps the aws-sdk-v2/config package and have tested this successfully locally: #132