Add 🀫 Back of Tile

From <https://commons.wikimedia.org/wiki/File:MJhide.svg>.
Specifically, the "23:21, 20 October 2019" version.
```
$ svgo --version
3.0.4

$ svgo MJhide.svg -o 🀫.svg

MJhide.svg:
Done in 44 ms!
34.945 KiB - 93.9% = 2.143 KiB
```