Always set Object Storage Direct Upload to On

Problem to solve

We recently had a customer using the cloud native charts, and they had disabled Direct Upload for Object Storage because they didn't fully realize all that it did.

This caused issues with CI as well as other parts of GitLab. We should try to avoid users falling into this situation.

Proposal

I believe we initially implemented this option when we were still iterating on Direct Upload and getting it stable and ready for production. It's now essentially a required flag for any deployment that is using gitaly without NFS.

Is there a reason why a customer would not want Direct Upload to be enabled? If not, could we remove the configuration option in future releases and always use Direct Upload with object storage?

This way we reduce the chances of a customer with a broken configuration because they did not realize the importance of this flag.