Jekyll warning with 404.html file when releasing a new version

[florentmaitre]

Each time a new version is released, a warning is added to the Jekyll server console:

Conflict: The following destination is shared by multiple files.
                The written file may end up with unexpected contents.
                /ods/ods-android/docs/_site/404.html
                 - 0.19.0/404.html
                 - 404.html