Point all image reference to Ironbank

Mimir images need to point to iron bank repository. Currently due to the values.yaml not in line with the downstream mimir values.yaml, further configuration is required.

mimir deployment spec

Acceptance Criteria

• Mimir images point to ironbank (do not include dependency chart images like mimir/grafana-agent/rollout_operator)
• Include Mimir Enterprise image (To show proof you can show screenshot of the manifest using helm template since Mimir enterprise image is not in ironbank, Remember to leave Mimir Enterprise disabled until Mimir enterprise image is in Ironbank)
• Include Mimir memcached Exporter image (To show proof you can show screenshot of the manifest using helm template since Mimir memcached Exporter image is not in ironbank, Remember to disable Mimir memcached Exporter until Mimir memcached Exporter image is in Ironbank)