If a DB migration occurs, there's a chance that the application settings are
loaded from the cache and provide stale values, causing Error 500s.
This ensures that at startup the settings are always refreshed.

Closes #3643

- Enable CI by default for all new projects

- Offloads uploading to GitLab Workhorse
- Use /authorize request for fast uploading
- Added backup recipes for artifacts
- Support download acceleration using X-Sendfile

[ci skip]

This option only existed to ease the CI-to-CE/EE migration process.

This commit partially reverts 8b05abe8

This adds support for AWS S3 SSE with S3 managed keys, this means the
data is encrypted at rest and the encryption is handled transparently to
the end user as well as in the AWS Console. This is optional and not
required to make S3 uploads work.

Closes #2335

This change helps system administrators who want to replicate
GitLab backup files without needing root permissions.