Fix issue with doku thinking that last update was in 2012

Minor touch up: https://www.dokuwiki.org/plugin:tokenbucketauth?s[]=tokenbucketauth says that last update was in 2012.

In update manager, doku complains about a more up to date version being available, but updating doesn't remove this at it is still the same exact plugin. This _should_ fix it, but may not.