Resolves: fdo#69925 Wiki Publisher Extension is not working

Regression from http://cgit.freedesktop.org/libreoffice/core/commit/?id=b80d8c695e6b6ded231e67ed9a80bcd1f1250c03
"compareTo" has been replaced by "==", so we compared the equality ot the pointers on the objects instead of the content of the strings
To make it simple and since we compare String objects, let's simply use "equals" method

Change-Id: I65bc1a87751297411fdbe722d3f49bce5e291638
(cherry picked from commit 9e2d1d21f9a58e320444f6eaea2f006530bbd2cb)
Signed-off-by: Michael Stahl <mstahl@redhat.com>