[LLD][COFF] On Windows, fix the date formatting in the 'incremental' test.

On my system the date formatting is a bit different from what the test used to
support. I'm using:

  Windows 11 version 21H2, build 22000.795 using the English(Canada) region.
  ls from BusyBox 1.36
  VS 2022 17.2.5
  WinSDK 10.0.22000