[NFCI] [ClangScanDeps] [P1689] Use PreprocessorOnly Action for P1689

It is fine enough to use PreprocessorOnly action for P1689 format. We
don't need to read any PCH or module files.

GitOrigin-RevId: 62fec3d23d2325869e6eba0263b0b9f834c2067f
1 file changed