Install toml extra for Python <3.11

Author: brianschubert

.github/workflows/ci.yml

@@ -70,7 +70,7 @@ jobs:
         if: ${{ !startsWith(matrix.python-version, 'pypy') }}
         run: |
           # Be wary that this does not install typing_extensions in the future
-          pip install coverage
+          pip install 'coverage[toml]'
 
       - name: Test typing_extensions with coverage
         if: ${{ !startsWith(matrix.python-version, 'pypy') }}