### Check existing issues - [x] I've verified that this request isn't described by any existing issues. ### Request The @canonical/solutions-qa team relies heavily on charm metadata in our automated charm testing pipelines in order to determine how to build a proper test bundle. Critically, we assume all endpoints that don't explicitly have `optional: true` are required, and this often results in extra charms pulled into tests that don't need to be there, which further increases the surface area for failures and often results in tests failing for reasons unrelated to the actual charm being tested. Observability endpoints are prime examples. They are almost never required for a charm to actually function. Marking endpoints like `logging`, `grafana-dashboard`, and `metrics-endpoint` as optional would significantly improve the accuracy and effectiveness of the charm integration testing initiative. The extensions generate metadata that don't mark these as optional, so we are requesting that the extensions get updated to add `optional: true` to the relevant endpoints. ### The problem it solves This solves the problem of larger-than-necessary charm bundles being deployed in the charm testing initiative, which increases the risk of irrelevant test failures, which in turn waste compute time.