Update test.yml

removing the old version of python, 3.6, and 3.7

.github/workflows/test.yml

@@ -15,8 +15,6 @@ jobs:
     strategy:
       matrix:
         python-version:
-          - 3.6
-          - 3.7
           - 3.8
           - 3.9
         include:
@@ -35,6 +33,7 @@ jobs:
           python-version: '${{ matrix.python-version }}'
       - name: Install dependencies
         run: |
+          pip install --upgrade pip
           pip3 install -r requirements.txt
           pip3 install .
           pip3 install coverage