Fix TestCommandScript.py for Arm/Windows

TestCommandScript.py fails on Arm/Windows due following issues:
https://llvm.org/pr56288
https://llvm.org/pr56292

LLDB fails to skip prologue and also step over library function or
nodebug functions fails due to PDB/DWARF mismatch.

This patch replace function breakpoint with line breakpoint so that we
can expect LLDB to stop on desired line. Also replace dwarf with PDB
debug info for this test only.