Comment 25 for bug 2065761

> The stg-github-runner-mq is not shown as having consume permission hence the permission denied errors.

That seems to fit:

juju-controller-34-staging-ps6@is-bastion-ps6:~$ juju show-offer stg-github-runner-mq.mongodb --format yaml
juju-controller-34-staging-ps6:admin/stg-github-runner-mq.mongodb:
  description: |
    MongoDB is a general purpose distributed document database. This charm
    deploys and operates MongoDB.
  access: admin
  endpoints:
    database:
      interface: mongodb_client
      role: provider
  users:
    admin:
      display-name: admin
      access: admin
    everyone@external:
      access: read
juju-controller-34-staging-ps6@is-bastion-ps6:~$ _

So in this case the `stg-github-runner-mq` user should run something like `juju grant stg-github-runner-webhook-router consume admin/stg-github-runner-mq.mongodb`?