Update main.yml

Author: asottile-sentry

.github/workflows/main.yml

@@ -14,4 +14,4 @@ jobs:
       - run: |
           set -x
           env | sort
-          python3 -c 'import psutil; print(sorted(psutil.Process.open_files()))'
+          python3 -c 'import psutil; print(sorted(psutil.Process().open_files()))'