[FEATURE] Add `RabbitMQ` health check

Enhance the existing C# ASP.NET API project by adding a RabbitMQ health check. This check will monitor the RabbitMQ service's status and integrate with the existing health checks system.

#### Requirements
- Use the [AspNetCore.HealthChecks.Rabbitmq](https://www.nuget.org/packages/AspNetCore.HealthChecks.Rabbitmq) NuGet package.
- Ensure the RabbitMQ health check is configured alongside the existing health checks without disrupting them.
- The health check endpoint should include the RabbitMQ status in its output.

#### Acceptance Criteria
- [ ] RabbitMQ health check successfully integrates using `AspNetCore.HealthChecks.Rabbitmq`.
- [ ] The health endpoint outputs the status of RabbitMQ alongside the API health.
- [ ] Appropriate error handling for scenarios where RabbitMQ is unavailable.
- [ ] Unit tests cover the RabbitMQ health check implementation.
- [ ] Documentation is updated to reflect the new health check configuration.

#### Notes
- Assume the health check for the API itself is already implemented.
- Ensure that the configuration for RabbitMQ (e.g., connection string) is securely managed (e.g., using environment variables or a configuration provider).

### References
- [RabbitMQ and .NET Core Health Checks](https://gregorbowie.wordpress.com/2020/02/08/rabbitmq-and-net-core-health-checks/)
- https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks/issues/480

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