Remove redundant python versions and fix test dep install

.github/workflows/testing.yml

@@ -8,7 +8,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.7", "3.8", "3.9", "3.10", "3.11"]
+        python-version: ["3.9", "3.10", "3.11"]
     steps:
     - uses: actions/checkout@v2
     - name: Set up Python
@@ -19,9 +19,9 @@ jobs:
       run: |
         python -m pip install --upgrade pip
         python -m pip install flake8
-        if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
-        if [ -f tests/requirements.txt ]; then pip install -r tests/requirements.txt; fi
-        python -m pip install -e .
+        # if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
+        # if [ -f tests/requirements.txt ]; then pip install -r tests/requirements.txt; fi
+        python -m pip install -e '.[test]' 
     - name: Lint with flake8
       run: |
         # stop the build if there are Python syntax errors or undefined names