much better to run this on ubuntu

Author: maxbelanger

.github/workflows/ci.yml

@@ -47,7 +47,7 @@ jobs:
         run: |
           pytest -v test/unit/test_dropbox_unit.py
   Docs:
-    runs-on: macos-13
+    runs-on: ubuntu-20.04
     steps:
       - uses: actions/checkout@v2
       - name: Setup Python environment