S3 Cache multipart upload for non-AWS services
Description
The new S3v2 cache provider only supports AWS, because it generates ARN roles that are specific to AWS.
This feature does not work with other providers such as MinIO, Hetzner Object Storage, Backblaze and so on.
Our caches would be used for Yocto which are more than 150 GiB.
Proposal
Add support for multipart upload of caches that are not dependent on AWS. Theoretically, the gitlab-runner could create a multipart upload and create n pre-signed URLs for each multipart.