editors/libreoffice: uopdate to 26.8.0 release (+)

The FreeBSD Office team is glad to announce the availability of LibreOffice 26.8,
the new major release of the free and open source office suite.

LibreOffice 26.8 brings professional typography, deeper support for the world’s writing systems, and no artificial intelligence

Announce: https://blog.documentfoundation.org/blog/2026/08/26/libreoffice-26-8/
Release notes: https://wiki.documentfoundation.org/ReleaseNotes/26.8