Fix: compile reciprocal_grid.cpp in deepks unit tests

The ReciprocalGrid refactor made K_Vectors derive from
ModuleCell::ReciprocalGrid, so klist.cpp.o and k_vector_utils.cpp.o now
reference ReciprocalGrid member functions and its vtable. The
deepks_unit_support object library (DEEPKS_UNIT_COMMON_SOURCES, gated
behind ENABLE_MLALGO and thus only compiled in the gnu Test CI job)
compiles klist.cpp without reciprocal_grid.cpp, failing to link all 30
MODULE_LCAO_DEEPKS_* test executables with undefined references to
ModuleCell::ReciprocalGrid::renew/Monkhorst_Pack/build_star_ops/... and
its vtable/typeinfo. Add the missing translation unit to the common
source set; the symmetry library (incl. little_group.cpp) is already on
the link line.

Author: Zanthoxylum

source/source_lcao/module_deepks/test/CMakeLists.txt

@@ -28,6 +28,7 @@ set(DEEPKS_UNIT_COMMON_SOURCES
     ../../../source_cell/klist.cpp
     ../../../source_cell/parallel_kpoints.cpp
     ../../../source_cell/k_vector_utils.cpp
+    ../../../source_cell/reciprocal_grid.cpp
     ../../setup_nonlocal.cpp
     ../../../source_cell/pseudo.cpp
     ../../../source_cell/read_pp.cpp