[gdk-pixbuf] tests: Add truncated GIF file with huge dimensions

[Bastien Nocera <hadess src gnome org>]

commit 140595d465ce9b46e9c287186d96012eca696987
Author: Bastien Nocera <hadess hadess net>
Date:   Wed Aug 23 18:16:42 2017 +0200

    tests: Add truncated GIF file with huge dimensions
    
    https://bugzilla.gnome.org/show_bug.cgi?id=785973

 tests/test-images/fail/bug785973.gif |  Bin 0 -> 102400 bytes
 1 files changed, 0 insertions(+), 0 deletions(-)
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diff --git a/tests/test-images/fail/bug785973.gif b/tests/test-images/fail/bug785973.gif
new file mode 100644
index 0000000..7f13510
Binary files /dev/null and b/tests/test-images/fail/bug785973.gif differ