* feat(precheck): add support for .gds.br compressed layouts
* fix(precheck): adapt the test suite to changed klayout_checks() signature
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Co-authored-by: htfab <mpw@htamas.net>
Flattened sky130 devices in analog layouts can lead to DRC errors.
They are difficult to test for, so as a heuristic we add a warning when magic DRC fails and there are no unflattened sky130 cells.