This script builds only libslic3r_tests, which links libslic3r and no GUI code —
but cmake still processed the whole if(SLIC3R_GUI) block and every find_package
inside it, so the kernel suite silently depended on the GUI's dependency set.
That came due the moment upstream added wxInspector as a REQUIRED find_package:
the orcacad-deps image predates it, so configure died pointing at
src/CMakeLists.txt:92 with nothing about the kernel having changed. Turning the
block off is not a workaround for that one dependency — it is the suite finally
declaring what it actually needs, so the next GUI-side dependency added upstream
cannot break it either.
Surfaced by taking SoftFever's merge of main into the PR branch.