Describe the Testing Issue

1. Building ABACUS with -DENABLE_PEXSI=ON has problem now:

Building CXX object source/source_lcao/module_hcontainer/CMakeFiles/hcontainer.dir/base_matrix.cpp.o
/abacus/source/source_lcao/edm.cpp(33): error #303: explicit type is missing ("int" assumed)
          auto pes = dynamic_cast<const elecstate::ElecStateLCAO<double>*>(pelec);
                                  ^

2. Unit tests related to PEXSI are needed.

Additional Context

No response

Task list for Issue attackers (only for developers)

• Understand the testing issue described by the developer.
• Review the specific test case, expected and actual results, and any error messages.
• Identify the root cause of the test failure or issue.
• If a possible solution is suggested, evaluate its feasibility and effectiveness.
• Implement a fix for the test failure or issue, or create a new test case if needed.
• Verify that the fix resolves the testing issue and the test case passes.
• Review and update any relevant documentation, such as test plans or user guides.
• Ensure the testing issue is resolved and close the ticket.
• Share any lessons learned or best practices with the team to prevent similar issues in the future.