Add IAM Role support for the AWS S3 fileserver

[lumattr]

Additional context
The S3 fileserver support has parameters here but the appear to use an access key and secret key parameter which goes against AWS best practice guidelines.

This function appears to use the parameters but would need to be updated to expect the environment vars for the different metadata contexts available in AWS, EKS, EC2 etc.

Is your feature request related to a problem? Please describe.
I would like to use the S3 filestore but i am unable to create an access key and secret from from an IAM user.

Describe the solution you'd like
I would like to be able to just add additional IAM polices to the service account configured by the Helm chart, that is used by the services in the console, that would provide the acces to the specified bucket.

Components/Services

• UI/Frontend
• API/Backend
• Agent
• Deployment/YAMLs
• CI/CD Integration
• Other (specify)