Handling of S3 session tokens

[fBedecarrats]

Hi @cboettig, thanks for this promising package! One question: what would be the right way to handle session tokens with it. I'm using a minio S3 services that requires providing such tokens (set with Sys.setenv("AWS_SESSION_TOKEN" = "mytoken") for {paws} or {aws.s3}). Is there a way to set up such tokens with {minioclient}? I could not find the information in the package documentation and my attempts were not successful.