Revert cache settings through Kubernetes secret in values yaml

What does this MR do?

In the MR !393 (merged) and !397 (merged) we remove the ability to set cache parameters through k8s secret.

With this MR, this functionality is brought back this ability.

Why was this MR needed?

To bring back ability to set cache parameters through k8s secret

What's the best way to test this MR?

In this test, I am used GCP and GCS.

Create gcsaccess

kubectl create secret generic gcsaccess  --from-literal=gcs-access-id="__GCS_ACCESS_ID__" --from-literal=gcs-private-key="__GCS_PRIVATE_KEY__"

values.yaml

image:
  registry: registry.gitlab.com
  image: gitlab-org/gitlab-runner
  # tag: ubuntu-bleeding
useTini: false
imagePullPolicy: IfNotPresent
replicas: 1
gitlabUrl: https://gitlab.com/
runnerToken: "__REDACTED__"
unregisterRunners: true

useJobNamespace: true
terminationGracePeriodSeconds: 0
concurrent: 1
checkInterval: 1
logLevel: "debug"
sessionServer:
  enabled: false
  annotations: {}
  timeout: 1800
  internalPort: 8093
  externalPort: 9000

## For RBAC support:
rbac:
  create: true
  rules: []
  clusterWideAccess: false
  serviceAccountName: ""
  serviceAccountAnnotations: {}
  podSecurityPolicy:
    enabled: false
    resourceNames:
    - gitlab-runner
metrics:
  enabled: true
  portName: metrics
  port: 9252
  serviceMonitor:
    enabled: false
service:
  enabled: false
  type: ClusterIP
runners:
  config: |
    [[runners]]
      [runners.cache]
        Type = "gcs"
        Path = ""
        Shared = true
        [runners.cache.gcs]
          BucketName = "touni-test-bucket"
      [runners.kubernetes]
        image = "alpine"
        [[runners.kubernetes.services]]
          name = "alpine:latest"
          alias = "alpine-service"
          command = ["sleep 900s"]
          entrypoint = ["/bin/sh", "-c"]
          # node_selector_overwrite_allowed = ".*"

  cache:
    ## Use this line for access using gcs-access-id and gcs-private-key
    secretName: gcsaccess
  builds: {}
  services: {}
  helpers: {}
securityContext:
  allowPrivilegeEscalation: false
  readOnlyRootFilesystem: false
  runAsNonRoot: false
podSecurityContext:
  runAsUser: 100
  fsGroup: 65533
resources:
  requests:
    memory: 128Mi
    cpu: 100m
affinity: {}
nodeSelector: {}
tolerations: []
hostAliases: []
podAnnotations: {}
podLabels: {}
hpa: {}
secrets: []
configMaps: {}
volumeMounts: []
volumes: []

gitlab-ci.yaml

variables:
  CACHE_FALLBACK_KEY: fallback-keys

build1:
  stage: build
  script:
    - ls -lah
    - cat cached-file.txt || echo "No file found"
    - echo "$(date)" > cached-file.txt
  cache:
    key: latest-cache-3
    policy: pull-push
    paths:
      - cached-file.txt
    fallback_keys:
      - latest-cache-2
      - latest-cache-1

The job succeeds and the cache is uploaded on GCS.

What are the relevant issue numbers?

close #460 (closed) #459 (closed) #457 (closed) gitlab-org/gitlab-runner#31078 (closed)