Xiaomi Mi full case replacement with AAA support

This is a full case replacement for the popular "Xiaomi Mijia Thermometer 2 Bluetooth Temperature Humidity Sensor"

It supports 2 AAA batteries as opposed to the default CR2032 cell. 

# Required Hardware
- The sensor
   https://www.aliexpress.com/item/1005006327843865.html

- A set of 9x9mm battery contacts (Square)
   https://www.aliexpress.com/item/1005003381661836.html 
   (The two little hooks on either side need to be pressed flat)

- 4mm, M3 (OD 5mm) Heat set insert for the battery cover.
   https://www.aliexpress.com/item/1005004535859664.html
   These are the same inserts sued by Voron printers.

Assembly is a little fiddly and requires some fine soldering skills, but the end result is pretty nice! 

These were printed on my Voron 2.4 from plane ESun ABS