chore: update migration-fixer.yml

Author: jackton1

.github/workflows/migration-fixer.yml

@@ -17,7 +17,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
-          python-version: '3.7.x'
+          python-version: '3.8.x'
           cache: 'pip'
           cache-dependency-path: '**/requirements.txt'