[gdk-pixbuf] tests: Add grayscale JPEG tests

[Bastien Nocera <hadess src gnome org>]

commit 4a4629496cf8a3116fec0838db89e0fb33c1568c
Author: Bastien Nocera <hadess hadess net>
Date:   Thu Jul 27 11:59:58 2017 +0100

    tests: Add grayscale JPEG tests
    
    Originally from the JPEG conformance tests:
    http://people.sc.fsu.edu/~jburkardt/data/jpg/jpg.html
    
    https://bugzilla.gnome.org/show_bug.cgi?id=785171

 tests/test-images/reftests/lena.jpg         |  Bin 0 -> 65591 bytes
 tests/test-images/reftests/lena.jpg.ref.png |  Bin 0 -> 249277 bytes
 2 files changed, 0 insertions(+), 0 deletions(-)
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diff --git a/tests/test-images/reftests/lena.jpg b/tests/test-images/reftests/lena.jpg
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diff --git a/tests/test-images/reftests/lena.jpg.ref.png b/tests/test-images/reftests/lena.jpg.ref.png
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