Remove closed poppler bugs from test/README

These bugs have all been closed resolved / fixed for years.

Reviewed-by: Bryce Harrington <bryce@osg.samsung.com>

test/README

@@ -278,42 +278,4 @@ the pdf-specific reference image.
 
 Here are the reported poppler bugs and the tests they affect:
 
-Poppler doesn't correctly handle gradients with transparency
-https://bugs.freedesktop.org/show_bug.cgi?id=12144
---------------------------------------------------
-fill-alpha-pattern
-gradient-alpha
-gradient-constant-alpha
-linear-gradient
-linear-gradient-reflect
-radial-gradient
-trap-clip
-
-Poppler should paint images with CAIRO_EXTEND_PAD
-https://bugs.freedesktop.org/show_bug.cgi?id=14578
---------------------------------------------------
-paint-source-alpha
-paint-with-alpha
-rotate-image-surface-paint
-scale-source-surface-paint
-
-Incorrect clipping of group object (regression?)
-https://bugs.freedesktop.org/show_bug.cgi?id=14580
---------------------------------------------------
-push-group
-
-spurious horizontal stripes in color gradients
-https://bugs.freedesktop.org/show_bug.cgi?id=10942
---------------------------------------------------
-smask 
-smask-fill 
-smask-image-mask 
-smask-mask 
-smask-paint 
-smask-stroke 
-smask-text
-
-Ghostscript does not correctly render small miters
-http://bugs.ghostscript.com/show_bug.cgi?id=690098
---------------------------------------------------
-miter-precision
+[Newest was closed in 2009.]