Fix: include parallel_comm.h for BP_WORLD in hsolver tests

test_hsolver_sdft.cpp and diago_bpcg_test.cpp use BP_WORLD without
including source_base/parallel_comm.h, which broke the MPI build.

Author: abacus_fixer

source/source_hsolver/test/diago_bpcg_test.cpp

@@ -7,6 +7,7 @@
 #include "../diago_bpcg.h"
 #include "diago_mock.h"
 #include "mpi.h"
+#include "source_base/parallel_comm.h"
 #include "source_basis/module_pw/test/test_tool.h"
 
 #include <gtest/gtest.h>

source/source_hsolver/test/test_hsolver_sdft.cpp

@@ -388,6 +388,7 @@ class TestHSolverPW_SDFT : public ::testing::Test
 // }
 
 #ifdef __MPI
+#include "source_base/parallel_comm.h"
 #include "source_base/timer.h"
 #include "mpi.h"
 int main(int argc, char** argv)