Corona Mill Cover - Reduced Bearing Support Cutouts for Generic Mills

This is a remix of the excellent Corona Mill cover with chute by wilbaar3. The cutouts needed on the sides to accommodate the bearing support were about 50% too big on my mill, resulting in ground grain spilling out through the gaps - see this make for a look at the problem area. I used MeshMixer to reduce the depth of the bearing cutouts by 5mm or around 50%, resulting in a tighter fit with the wider bearing support on my generic (not name-brand Corona) mill.