Use Opensearch to filter GitLab Dedicated logs by HTTP response status code

Why is this change being made?

This MR updates the GitLab Dedicated logs workflow in order to provide guidance on filtering logs by their HTTP response status code.

This is an important early troubleshooting step for Support Engineers working on GitLab Dedicated tickets. Making sure they have the information needed to filter logs by HTTP response status code will make it easier to achieve FRT and NRT goals on GitLab Dedicated tickets.

Related Efforts

• gitlab-com/gl-infra/gitlab-dedicated&212
• gitlab-com/support/support-pairing#10346

Author Checklist

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