feat(ruler): enables ruler store that uses clients from thanos-io/objstore pkg

[ashwanthgoli]

What this PR does / why we need it:

Rulers already have the necessary code to use the objstore clients created from thanos-io/objstore pkg.

This pr exposes the ruler_storage block which enables users to configure these clients. This is similar to how mimir ruler storage is configured and helps keep the configuration more consistent across the projects.

• adds s3 SSE overrides to configure server-side encryption for specific tenant
• configdb related code is removed since loki never supported it.

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

• docs for ruler_storage are marked hidden. It will be enabled along with other thanos object store blocks before the next minor release along with addition of deprecation notes for existing clients
• bucket_client_test.go already tests the modules wrapping both objectClient and bucket interfaces

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
• CHANGELOG.md updated
  • If the change is worth mentioning in the release notes, add add-to-release-notes label
• Changes that require user attention or interaction to upgrade are documented in docs/sources/setup/upgrade/_index.md
• For Helm chart changes bump the Helm chart version in production/helm/loki/Chart.yaml and update production/helm/loki/CHANGELOG.md and production/helm/loki/README.md. Example PR
• If the change is deprecating or removing a configuration option, update the deprecated-config.yaml and deleted-config.yaml files respectively in the tools/deprecated-config-checker directory. Example PR