RAG stack showing incorrect display name for signing_key

Incorrect display name here -> https://github.com/terraform-ibm-modules/stack-retrieval-augmented-generation/blob/97a51cd90aa37121fdb03cbd3801062929d57f9c/ibm_catalog.json#L238

Rending in UI like this:

<img width="497" alt="Image" src="https://github.com/user-attachments/assets/2574284a-01dd-45da-8628-40cd7b62d06b" />