update workflow

Author: nghia-vo

.github/workflows/discorpy_ga.yml

@@ -37,7 +37,7 @@ jobs:
 
     - name: Upgrade pip on macOS only
       if: runner.os == 'macOS'
-      run: python3.8 -m pip install --upgrade pip
+      run: python -m pip install --upgrade pip
 
     - name: Install dependencies
       run: |