Describe the bug

• Upgrading to the Helm Chart 6.45.1 (from 6.44.0) fail when memcached.image.repository is set
• global.imageRegistry don't set the registry for Loki images

To Reproduce

Steps to reproduce the behaviour:

1. Install Loki via the Helm chart (version 6.44.0), using the default value below
2. Update to the Helm chart version 6.45.1 (current latest)
3. Memcached can't start because the image is <registry>/<registry>/memcached:1.6.39-alpine (note the double registry here)

Furthermore, configuring global.imageRegistry only, is basically ignored and registry is not set (global.image.registry works well)

I guess it can be expected for Memcached as the attribute is repository not registry, but it is still a breaking change, and global.imageRegistry just doesn't set the registry

global:
  image:
    registry: "europe-docker.pkg.dev/xxxx/docker-public"

memcached:
  image:
    repository: "europe-docker.pkg.dev/xxxxx/docker-public/memcached"

memcachedExporter:
  image:
    repository: "europe-docker.pkg.dev/xxxx/docker-public/prom/memcached-exporter"

deploymentMode: Distributed

Expected behaviour
Upgrade should succeed without update the values.yaml

Environment:

• Infrastructure: Kubernetes (GKE)
• Deployment tool: Helm

Workaround:

Keep global.image.registry instead of global.imageRegistry and remove memcached.image.repository / memcachedExporter.image.repository -> registry will be set correctly for all images