Hygrometer for Filament Dryer Esun Ebox Lite rear

Some small changes to the great design of @vivamus3d https://www.printables.com/model/274551-hygrometer-for-filament-dryers-sunlu-s1-and-esun-e/files, allowing the mounting plate to be put at the back (where the lid hinge is) of an Esun Ebox Lite. Lift up the metal plate slightly by hand and slip it in - make sure the cutout in the middle is snug arount the ridges for the hinge.

Also removed more material at the sides, because my large spools was otherwise dragging on it…. This is bad for rigidity etc - but once in place it isn't under much stress.

Any build instructions for the original go for this one as well, and should retain full compatibility with all the hygrometer holders that slip into this mounting plate, but only tested with the round model.

All kudos to @vivamus3d!