Hygiene: Merge identical $wgMFEnableMinervaBetaFeature and $wgMFDesktopMinerva

Erg.

Change-Id: I90a11cd4061268b048a80abd9787ad9bdebeaece
Merge "Hygiene: Merge identical $wgMFEnableMinervaBetaFeature and $wgMFDesktopMinerva"