increase nbval timeout

Author: Mridul Seth

.github/workflows/build.yml

@@ -17,7 +17,7 @@ jobs:
       max-parallel: 12
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
-        python-version: [3.6, 3.7, 3.8]
+        python-version: [3.7, 3.8]
 
     steps:
     - uses: actions/checkout@v1
@@ -32,4 +32,4 @@ jobs:
     - name: Test with nbval
       run: |
         pip install pytest
-        pytest --nbval-lax --nbval-cell-timeout=1200 notebooks/
+        pytest --nbval-lax --nbval-cell-timeout=12000 notebooks/