Description of problem:

Incorrect indentation for the additionalImages stanza in the ImageSetConfiguration object leads to an error from oc-mirror

additionalImages needs to be at the same column as operators per the examples in the OCP docs like the ImageSetConfiguration example at https://docs.redhat.com/en/documentation/openshift_container_platform/4.21/html/disconnected_environments/about-installing-oc-mirror-v2#oc-mirror-building-image-set-config-v2_about-installing-oc-mirror-v2 

Prerequisites (if any, like setup, operators/versions):

Steps to Reproduce

 An invocation like 

```

gmontero ~/go/src/github.com/redhat-developer/rhdh-operator  (air-gap-lt-spd)$ bash .rhdh/scripts/prepare-restricted-environment.sh -install-operator false  -use-oc-mirror true   --to-registry quay.io/gabemontero/rhdh   --filter-versions "1.8" --extra-images quay.io/lightspeed-core/lightspeed-stack:0.4.0,quay.io/redhat-ai-dev/llama-stack:0.1.4,quay.io/redhat-ai-dev/rag-content:release-1.9-lcs

```

Actual results:

GGM start oc-mirror in to registry path with registry url quay.io/gabemontero/rhdh and flags
GGM start cat imageset-config.yaml
apiVersion: mirror.openshift.io/v2alpha1
kind: ImageSetConfiguration
mirror:
  operators:
  - catalog: registry.redhat.io/redhat/redhat-operator-index:v4.18
    full: false
    targetCatalog: rhdh-catalog
    packages:
      - name: rhdh
        channels:
          - name: fast
          - name: fast-1.8
      additionalImages:
      - name: "quay.io/lightspeed-core/lightspeed-stack:0.4.0"
      - name: "quay.io/redhat-ai-dev/llama-stack:0.1.4"
      - name: "quay.io/redhat-ai-dev/rag-content:release-1.9-lcs"
GGM end cat imageset-config.yaml
2026/03/02 15:40:58  [INFO]   : 👋 Hello, welcome to oc-mirror
2026/03/02 15:40:58  [INFO]   : ⚙️  setting up the environment for you...
2026/03/02 15:40:58  [ERROR]  : [Executor] failed to unmarshal config: error converting YAML to JSON: yaml: line 12: did not find expected '-' indicator

Expected results:

Reproducibility (Always/Intermittent/Only Once):

Build Details:

I ran this with commit level a5b22571b0564d10317f4b9330ce6c3785c448e2 from the rhdh-operator repo (March 2)

Additional info (Such as Logs, Screenshots, etc):

I have a fix in hand