tests: use `yosys-config --datdir` instead of hard-coded
tests: use `yosys-config --datdir` instead of hard-coded

SymbiFlow/yosys,YosysHQ/yosys,antmicro/yosys,cliffordwolf/yosys,cliffordwolf/yosys,antmicro/yosys,antmicro/yosys,cliffordwolf/yosys,SymbiFlow/yosys,antmicro/yosys,YosysHQ/yosys,SymbiFlow/yosys,cliffordwolf/yosys,cliffordwolf/yosys,cliffordwolf/yosys,antmicro/yosys,cliffordwolf/yosys,antmicro/yosys,YosysHQ/yosys,YosysHQ/yosys,SymbiFlow/yosys,YosysHQ/yosys,SymbiFlow/yosys,YosysHQ/yosys,cliffordwolf/yosys,YosysHQ/yosys,cliffordwolf/yosys,SymbiFlow/yosys,SymbiFlow/yosys,YosysHQ/yosys,SymbiFlow/yosys,antmicro/yosys,antmicro/yosys