Disable x-checker for modules tracking commits

[bbhtt]

This will be blocked in linter.

Affected modules: carla, backtrace, zix

[vchernin]

@alex-tee will any of these modules be needed in the zrythm qt rewrite? If so we should maybe check if the released versions actually work with zrythm.

[alex-tee]

@vchernin
backtrace won't be needed. Not 100% sure about carla and zix.

For the current v1 release, the latest release of zix would do but for carla the unreleased commit is still required.

[bbhtt]

You can pin it to a commit if you need a specific unreleased commit, it doesn't need to track the latest commits via x-checker.