Remove no longer needed notice in README

Author: consideRatio

README.md

@@ -16,10 +16,6 @@ This package formerly included WrapSpawner and ProfilesSpawner, which provide me
 
 ## Installation
 
-> **⚠ NOTE**
->
-> If you are using JupyterHub 3+ then you currently must install from the main branch, for example by `pip install https://github.com/jupyterhub/batchspawner/archive/main.zip`, due to a [bug that is resolved but not yet released](https://github.com/jupyterhub/batchspawner/issues/277).
-
 1. from root directory of this repo (where setup.py is), run `pip install -e .`
 
    If you don't actually need an editable version, you can simply run