Update some expected results for corpus testing.

The PDF rendering process was modified to draw diagonal thin lines formed
by overlapping path(https://pdfium-review.googlesource.com/57311/) and
this change will affect the AGG rendering results and cause failures in
corpus test. Need to update the failing corpus testing results with the
new AGG process.

Bug: pdfium:1338
Change-Id: I6796885fff37ee942344d00db465b8ba18f39d77
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium_tests/+/57356
Reviewed-by: Lei Zhang <thestig@chromium.org>