[loki] issue upgrading from 6.26.0 to 6.27.0

[lpaturel]

New version 6.27.0 seems to add an issue with the labels of the components.

In my chart values, on each component, I add a label called "affinity" with the pattern "loki-${component}" for anti-affinity calculation because I also have Mimir and Tempo on my nodes and each one of them having same component names (mimir-distributed and tempp-distributed).

So, with 6.26.0, labels are added correctly and everything seem to work fine.
But with 6.27.0, every component have the same labels with value 'loki-query-scheduler' instead of their own component, which prevent my ingesters (4 of them on 4 nodes) to boot. This issue seems to be located on every single component.

example of component in Helm Chart ->

ingester:
  extraArgs: ["-config.expand-env=true"]
  extraEnvFrom:
    - secretRef:
        name: loki-s3-credentials
  nodeSelector:
    nodepool: lgtm-nodepool
  replicas: 4
  maxUnavailable: 1
  affinity:
    podAntiAffinity:
      requiredDuringSchedulingIgnoredDuringExecution:
        - labelSelector:
            matchLabels:
              affinity: loki-ingester
          topologyKey: kubernetes.io/hostname
  podLabels:
    affinity: loki-ingester
  resources:
    limits:
      cpu: 5
      memory: 24Gi
    requests:
      cpu: 1250m
      memory: 8Gi
  persistence:
    enabled: true
    claims:
      - name: data
        size: 25Gi
  zoneAwareReplication:
    enabled: false

which leads to following result with 6.26.0 ->

and with 6.27.0 ->

---

So after reading the templates, there's a diff on the way the labels are calculated with a new merge between loki.podLabels and ${component}.podLabels instead of dealing with each of them separately.