Add IAM users S3 access

[kenoir]

Following request from digital production, see: https://wellcome.slack.com/archives/C02ANCYL90E/p1730110827368179

Note: as this is a public project, we intentionally omit the names of the individuals these requests are for in this ticket.

• [ ] https://github.com/wellcomecollection/iam-users/pull/32
• [ ] https://github.com/wellcomecollection/iam-users/pull/33