Shorten POTD provider names and remove description that is not used anywhere

Summary:
QtQuick Controls 2 ComboBox doesn't handle long option well. Short names can solve the issue of D25354.

{F7769836}

The ComboBox is the only place that the names are used. The "Description"s aren't used anywhere and they are mostly the repeat of "Name"s. So I removed "Description" field.

Reviewers: #plasma, ngraham

Reviewed By: ngraham

Subscribers: plasma-devel

Tags: #plasma

Differential Revision: https://phabricator.kde.org/D25369