[tf] Update the outputs.tf with endpoints nomenclature

[MichaelThamm]

Summary

To remove implementation detail of the TF module when another module inherits it, it makes sense to replace the requires and provides output variables with endpoints.

Tandem PRs:

• [tf] Update the outputs.tf with endpoints nomenclature catalogue-k8s-operator#145
• [tf] Update the outputs.tf with endpoints nomenclature grafana-k8s-operator#356
• [tf] Update the outputs.tf with endpoints nomenclature traefik-k8s-operator#421
• [tf] Update the outputs.tf with endpoints nomenclature loki-coordinator-k8s-operator#20
• [tf] Update the outputs.tf with endpoints nomenclature loki-worker-k8s-operator#32
• [tf] Update the outputs.tf with endpoints nomenclature mimir-coordinator-k8s-operator#86
• [tf] Update the outputs.tf with endpoints nomenclature mimir-worker-k8s-operator#81
• [tf] Update the outputs.tf with endpoints nomenclature tempo-coordinator-k8s-operator#71
• [tf] Update the outputs.tf with endpoints nomenclature tempo-worker-k8s-operator#49

Testing

This was validated locally by changing the module references to my local FS and running terraform validate to ensure the endpoints are correctly referenced

[sed-i]

Looks good overall.
Wdyt about splitting the provides and requires using comments? I.e.

# provides:
endpoint1
endpoint2

# requires:
endpoint3
endpoint4