enable multipleAuthProviders by default
Created by: sqs
This feature flag shipped default disabled 3 releases ago. No issues have been reported. It is now changed to default enabled. In the following major release, the feature flag will be removed and multipleAuthProviders will always be enabled.
The goal is to reduce complexity of auth code by removing cases. The special-case of 1 auth provider doesn't add much complexity, but it's still good to remove one case.
This only applies to Enterprise.
This PR updates the CHANGELOG.md file to describe any user-facing changes.