What were you trying to do that didn't work?

Build a customized RHEL system

What is the impact of this issue to you?

It makes troubleshooting images more complicated.

Please provide the package NVR for which the bug is seen:

weldr-client-35.12-2.el9.x86_64

osbuild-composer-118-2.el9_5.x86_64

How reproducible is this bug?:

always

Steps to reproduce

1. Create a TOML file with a non-existing customization (e.g. `[customization.services]` instead of `[customizations.services]`)
2. Build the image using `composer-cli start`
3. Deploy and check the resulting image

Expected results

If the TOML file contains incorrect/invalid/unknown customizations `composer-cli` should present a warning or even abort the build before it starts.

Actual results

The image is built successfully, no warning is shown, the deployed system does not contain the expected results.