[VIM] Typo in researcher credits for "file" vulnerability

[Steven M. Christey]

  MLIST:[file] 20070302 file-4.20 is now available
  URL:http://mx.gw.com/pipermail/file/2007/000161.html
  CONFIRM:https://bugs.gentoo.org/show_bug.cgi?id=171452

The original vendor disclosure credited "Jean-Sebastien Guay-Lero,"
and this cascaded everywhere.  But it's most likely "Jean-Sebastien
Guay-Leroux," who's reported a few issues in the past.

- Steve