The 40-character bookmark name truncation for MSO was
applied on percent encoded Unicode letters, resulting
shorter bookmark names, than needed (for example,
only 6 letters instead of 40).

This is a clean-up of the commit b9afb995
"tdf#113483: DOCX: fix encoding of bookmarks with non-ASCII letters".

Change-Id: I6fbcdc47c57ef228abcf29e0a68d3d8bb66c5661
Reviewed-on: https://gerrit.libreoffice.org/72456Tested-by: László Németh <nemeth@numbertext.org>
Tested-by: Jenkins
Reviewed-by: László Németh <nemeth@numbertext.org>