make: Fix archive_cpp target

Author: Mizux

makefiles/Makefile.cpp.mk

@@ -249,7 +249,7 @@ else
 endif
 endef
 
-CPP_SAMPLES := algorithms graph glop constraint_solver linear_solver math_opt model_builder pdlp routing sat
+CPP_SAMPLES := algorithms graph glop constraint_solver linear_solver math_opt model_builder pdlp routing sat set_cover
 $(foreach sample,$(CPP_SAMPLES),$(eval $(call cpp-sample-target,$(sample))))
 
 # Examples