Update all bootc and instructlab application images to use latest RHELAI RPMs.

Acceptance criteria:

• image uses latest RHELAI repo version
• repos use official repo ids, e.g. "rhelai-1.5-for-rhel-9-x86_64-rpms" for production CDN
• remove references to nightly composes and delete Red_Hat_IT_Root_CA.crt
• new mandatory RPMs are installed
• deprecated and removed RPMs are no longer installed

bootc:

• https://gitlab.com/redhat/rhel-ai/containers/amd-bootc
• https://gitlab.com/redhat/rhel-ai/containers/intel-bootc
• https://gitlab.com/redhat/rhel-ai/containers/nvidia-bootc

application:

• https://gitlab.com/redhat/rhel-ai/containers/instructlab-amd
• https://gitlab.com/redhat/rhel-ai/containers/instructlab-intel
• https://gitlab.com/redhat/rhel-ai/containers/instructlab-nvidia