Add JOSS and github stars badge to readme (#623)

Author: jan-janssen

README.md

@@ -2,6 +2,8 @@
 [![Pipeline](https://github.com/pyiron/executorlib/actions/workflows/pipeline.yml/badge.svg)](https://github.com/pyiron/executorlib/actions/workflows/pipeline.yml)
 [![codecov](https://codecov.io/gh/pyiron/executorlib/graph/badge.svg?token=KFIO3R08H3)](https://codecov.io/gh/pyiron/executorlib)
 [![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2/gh/pyiron/executorlib/HEAD)
+[![status](https://joss.theoj.org/papers/7a4bced702e5ea10e4630bc4d5dbaad2/status.svg)](https://joss.theoj.org/papers/7a4bced702e5ea10e4630bc4d5dbaad2)
+![GitHub Repo stars](https://img.shields.io/github/stars/pyiron/executorlib)
 
 Up-scale python functions for high performance computing (HPC) with executorlib.