[helm chart] Loki pod annotations in gateway

[blezoray]

Describe the bug
When i configure "Prometheus" annotations in "loki" section values:

# @default -- See values.yaml
loki:
...
  # -- Common annotations for all pods
  podAnnotations:
    prometheus.io/scrape: "true"
    prometheus.io/port: "3100"
...

the gateway deployment has these annotations and it generates alerts because it has no exporter on port 3100.

❯ k get deployment/loki-gateway -o yaml| yq .spec.template.metadata.annotations
checksum/config: 2a3f137dea8f98982978b976f1e74758853372f5ff6d83c9c46ebb0a490dc358
prometheus.io/port: "3100"
prometheus.io/scrape: "true"

Gateway deployment should not have "loki" annotations but only its owned annotations.

Code: https://github.com/grafana/loki/blob/main/production/helm/loki/templates/gateway/deployment-gateway-nginx.yaml#L34-L36

Environment:

• Infrastructure: Kubernetes
• Deployment tool: helm-loki-6.28.0

[blezoray]

@trevorwhitney , @jeschkies : FYI.