add yarn to binder

bollwyvl · bollwyvl · commit 9ae8feed4caa · 2021-02-22T11:26:07.000-05:00
diff --git a/.binder/environment.yml b/.binder/environment.yml
@@ -9,6 +9,7 @@ dependencies:
   - pip
   - wheel
   - setuptools
+  - yarn <2
   # dependencies
   - ipydatawidgets >=1.1.1
   - ipywidgets >=7.2.1
