Describe the bug

Some of the built-in Cheetah Templates and Snippets have not been updated to include via the built-in prefix.

Steps to reproduce

1. Try to use a built-in template or snippet that uses the $SNIPPET syntax
2. See issue

Expected behavior

The snippets render successfully. To fix the issue, tests should be added that attempt a basic rendering of all templates and snippets.

Cobbler version

19af9018c85973c5a9b8625130610d9dd0db07cb

Operating system

openSUSE Leap

Cobbler log

Not relevant

Screenshots

None

Additional information

Found during the work on #3293