feat: add s3 support for blockstore and datastore

[azf20]

Description

Letting users use S3 for their blockstore and datastore by adding additional S3-related environment variables

Notes & open questions

• This includes a patch of this s3-datastore issue datastore-s3 throws the wrong error when a file isn't found on s3 js-stores#331

Change checklist

• I have performed a self-review of my own code
• I have made corresponding changes to the documentation if necessary (this includes comments as well)
• I have added tests that prove my fix is effective or that my feature works