Ruler: Disable x-scope-orgid header append in remote write

[jburnham]

What this PR does / why we need it:
Adds option to disable addition of X-Scope-OrgID header in ruler remote write config. Needed to remote write to Amazon Managed Prometheus (Cortex).

Which issue(s) this PR fixes:
I suspect (but cannot prove) this will add a workaround for this existing open issue #9438

Special notes for your reviewer:
This is a similar PR from the Tempo project where it could not remote write to Amazon Managed Prometheus. We were having the same issues with the X-Scope-OrgID header that now works once this header is disabled.
Related issue from Tempo project

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

[jburnham]

Had an open ticket with AWS about this behavior and received the following reply.

The AMP team has confirmed this is expected behavior, and applications should remove this header from their remote write requests to AMP.

They then also linked to this PR.

[dannykopping]

LGTM, with a minor nit.

[jburnham]

@dannykopping I ran make format to fix the Drone CI check.

[dannykopping]

Thanks for your contribution @jburnham 👍