Document BUILDKITE_S3_PROFILE with v3.111.0 and above. #3636
Description
With v3.110.0 and below, artifact_paths or buildkite-agent artifact upload ... used to use default profile to authenticate to our S3.
After the upgrade to v3.111.0 and above, the agent started using AWS_PROFILE available in its environment. To overcome this issue, We had to rely on BUILDKITE_S3_PROFILE variable. This variable is not documented (https://buildkite.com/docs/agent/v3/cli-artifact#using-your-private-aws-s3-bucket-credentials) for end users, but I found this variable from this code base to force buildkite to use certain AWS profile.
Can the usage and availability of BUILDKITE_S3_PROFILE documented, so that users can avoid their AWS_PROFILE being picked up for BK related actions?