Previously we used a symetric image to test JPEG import. This has
the flaw that we doesn't warn if the orientation of the JPEG
image was not correct. This commit fixes this flaw by making all
test images non-symetrical.

Change-Id: If87d257ae44d85b6a9042d09d62ba785ffc5c426
Reviewed-on: https://gerrit.libreoffice.org/30709Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>