Update python-dev.yml

Author: jonashaag

.github/workflows/python-dev.yml

@@ -61,7 +61,7 @@ jobs:
         #pip install -i https://pypi.anaconda.org/scipy-wheels-nightly/simple numpy
         pip install numpy
         pip install git+https://github.com/nedbat/coveragepy.git
-        pip install cython python-dateutil pytz hypothesis pytest>=6.2.5 pytest-xdist pytest-cov
+        pip install cython python-dateutil pytz hypothesis pytest>=6.2.5 pytest-xdist pytest-cov pytest-asyncio
         pip list
 
     - name: Build Pandas