Windows dump_crash_context take reference to crash_context

[Will-MingLun-Li]

dump_crash_context only read values of CrashContext, so we can just pass in the reference and don't need to pass the value. This is useful when used with crash handler.

For example, currently the code below wouldn't work, and crash_context can't be converted to type CrashContext since it doesn't implement Copy trait

  CRASH_HANDLER
      .set(
          crash_handler::CrashHandler::attach(unsafe {
              crash_handler::make_crash_event(|crash_context| {  // <- This is of type &CrashContext
                  let mut minidump_file = std::fs::File::create("dump.mdmp").expect("failed to create file");

                  minidump_writer::minidump_writer::MinidumpWriter::dump_crash_context(
                      crash_context,
                      None,
                      &mut minidump_file,
                  );

                  crash_handler::CrashEventResult::Handled(false)
              })
          })
          .expect("CrashHandler should be initialized"),
      )
      .expect("CRASH_HANDLER should be set");