Prusa PSU replacement frame brace

Remix of the frame brace used in _the_ [Prusa enclosure](https://www.youtube.com/watch?v=oS7ZtBNh2hE). Pretty simple, just thought it was a lot of plastic going to waste in the original one, so cut out the centre to try and reduce plastic usage.

Cut out as much as i thought i could and still have it solid. The part came out really strong, so could probably shave off a lot more on the insides and on the two panels that get bolted to the frame.

Also used 50% infill which was probably unnecessary and could probably cut that back down to the standard ~20%.

Made from PLA and works well. Haven't noticed the print enclosure temperature having any effect on its strength, but ABS would probably be better suited to this part.

If you really want to save plastic though, shoutout to [EwoutG's design](https://www.thingiverse.com/thing:2883827) which smartly moves the part the brace attaches to.