ENH: Update notebook tests to use nbmake-action

Author: thewtex

.github/workflows/notebook-test.yml

@@ -9,7 +9,7 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-python@v2
-      - uses: treebeardtech/treebeard@v0.1.1
+      - uses: treebeardtech/nbmake-action@v0.2.1
         with:
           docker-username: thewtex
           docker-password: "${{ secrets.DOCKER_PASSWORD }}"