Improve caching used in GH actions

**What happened**:
Setup action sometimes fails on (cache restore?) when it tries to access a symlink from one of the GL feature directories. This can break nightly builds: https://github.com/gardenlinux/gardenlinux/issues/3882

**What you expected to happen**:

**How to reproduce it (as minimally and precisely as possible)**:

**Anything else we need to know**:

**Environment**:
