Reading SwWW8ImplReader::CoreLoad()'s "update graphic bullet
information" block, it turns out that the numbering picture bullet's
height should be independent from the supplied bitmap, and only its
aspect ratio should be respected.

(cherry picked from commit eab89b7f)

Change-Id: I1300aa0397a8098df2a3170af795fbba47fd2a9e
Reviewed-on: https://gerrit.libreoffice.org/16502Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Christian Lohmaier <lohmaier+LibreOffice@googlemail.com>