check min requirements (#70)

.github/workflows/test_and_deploy.yml

@@ -136,6 +136,28 @@ jobs:
           name: screenshots ${{ runner.os }}
           path: screenshots
 
+  test_old_qtpy:
+    name: qtpy minreq
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: tlambert03/setup-qt-libs@v1
+      - uses: actions/setup-python@v2
+        with:
+          python-version: '3.8'
+
+      - name: install
+        run: |
+          python -m pip install -U pip
+          python -m pip install -e .[testing,pyqt5]
+          python -m pip install qtpy==1.1.0 typing-extensions==3.10.0.0
+
+      - name: Test napari magicgui
+        uses: GabrielBB/xvfb-action@v1
+        with:
+          run: python -m pytest --color=yes
+
+
   test_napari:
     name: napari tests
     runs-on: ubuntu-latest