Add details to why the minio tenant headless service must be used over the normal clusterIP service

["The console service is for managing the tenant, while the hl service exposes the S3 compatible API. "](https://cloudnative-pg.io/plugin-barman-cloud/docs/object_stores/#minio-object-store)

the `-hl` service is a headless service. There is also a `minio` "normal" (clusterIP) service created. Why can't we used the "normal" service? Does the plugin have to connect to all of the pods behind the service? I have been testing with a single pod and it works with the normal service (not the headless version) but that may just be because there is a single pod. Can you update the docs to say why it can't use the normal service, if indeed that is the case? Thanks!

EDIT: Furthermore, how does https://cloudnative-pg.io/plugin-barman-cloud/docs/retention/ ("The Barman Cloud Plugin supports automated cleanup of obsolete backups via retention policies, configured in the .spec.retentionPolicy field of the ObjectStore resource.") square with https://cloudnative-pg.io/plugin-barman-cloud/docs/object_stores/#s3-lifecycle-policy ("Barman Cloud uploads backup files to S3 but does not modify or delete them afterward. ") ?

Comienza con las páginas de documentación enlazadas sobre los almacenes de objetos MinIO y la retención. Verifica por qué se requiere el tenant headless service en comparación con el ClusterIP service, y reconcilia la redacción de la política de retención con la afirmación sobre la política de ciclo de vida de S3. Se considera terminado cuando la documentación explica claramente el servicio compatible y presenta un comportamiento de retención coherente.

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