Close #10345. Add prometheus_rabbitmq_federation_collector. (backport #10721)

[mergify]

rabbitmq_federation_links gauge metric with status lable.

Proposed Changes

Types of Changes

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• Bug fix (non-breaking change which fixes issue #NNNN)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause an observable behavior change in existing systems)
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• Cosmetic change (whitespace, formatting, etc)
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Further Comments

TODO:

• use prometheus_model.hrl here https://github.com/rabbitmq/rabbitmq-server/pull/10721/files#diff-92763332116f8ec0bc16118ab302a440e5bbce16f2c972a75f0583ee00a36521R82
• explore adding more queues to federation for better counter check

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This is an automatic backport of pull request #10721 done by [Mergify](https://mergify.com).