Create recipe.yaml for simplejson

[tylere]

This should fix #456

[proppy]

Looking at the CI logs it doesn't look like anything is being built:

2023-05-13T15:51:09.6806670Z Extracting download
2023-05-13T15:51:09.6807056Z 
2023-05-13T15:51:09.6807333Z Preparing environment for simplejson
2023-05-13T15:51:09.6807744Z 
2023-05-13T15:51:09.6816232Z 
2023-05-13T15:51:09.6816472Z Starting build for simplejson
2023-05-13T15:51:09.6816752Z 
2023-05-13T15:51:09.6832498Z source tree in: 
2023-05-13T15:51:09.6833222Z /home/runner/micromamba-root/envs/ci-env/conda-bld/simplejson-0_1683993068571/wo
2023-05-13T15:51:09.6833631Z rk
2023-05-13T15:51:09.7308385Z number of files: 0
2023-05-13T15:51:09.7308669Z Fixing permissions
2023-05-13T15:51:09.7309843Z 
2023-05-13T15:51:09.7310287Z Adding files for simplejson
2023-05-13T15:51:09.7310626Z 
2023-05-13T15:51:09.7314134Z ATTENTION: No files added in target simplejson
2023-05-13T15:51:09.7316084Z 
2023-05-13T15:51:09.7316105Z