wizards: fix javadoc error: unknown tag: returns

Change-Id: I3d10c48a5fac2683f76cf21ef5c746377ca9a8c4
Reviewed-on: https://gerrit.libreoffice.org/11238
Reviewed-by: Thomas Arnhold <thomas@arnhold.org>
Tested-by: Thomas Arnhold <thomas@arnhold.org>