Caching issue while reorder sorting

I found this issue while debugging drag&drop sorting of a mm_* table in the backend.

This is the method used to reorder the sorting field in metamodels:
https://github.com/MetaModels/DC_General/blob/master/system/modules/generalDriver/GeneralControllerDefault.php#L1706

After the call of `reorderSorting`, the sorting field gets fetched again (from cache) and produces a wrong sorting, because of the cached result set from before sorting.

If I use `executeUncached(...)` on `fetchRows(...)` it works as expected.

Thx to @discordier & @stefanheimes