Code review comment for lp:~widelands-dev/widelands/list-directories-in-cpp

I got ~100 compile warnings:

src/io/filesystem/filesystem.h:150:71: warning: unknown command tag name [-Wdocumentation-unknown-command]
        /// Returns all files in the given 'directory' that match 'basename[_\d{1,3}].extension'
                                                                             ^~