XWIKI-22626: Long file names collide with elements from the right side on Office Importer on Firefox (#3761) (#3939)

* Fixed the overflow by adding a max-width. This is a safe change that will only act when there's an overflow. The regular use case shouldn't be influenced by this change.

(cherry picked from commit 83139b92)

Co-authored-by: LucasC <lucas.charpentier@xwiki.com>