Update io_file.yml

Author: brianquinlan

.github/workflows/io_file.yml

@@ -45,7 +45,7 @@ jobs:
       - uses: dart-lang/setup-dart@e51d8e571e22473a2ddebf0ef8a2123f0ab2c02c
         with:
           sdk: ${{ matrix.sdk }}
-      - run: dart --reporter=failures-only --test-randomize-ordering-seed=random --platform vm
+      - run: dart test --reporter=failures-only --test-randomize-ordering-seed=random --platform vm
 
   profile-vm-test:
     # Ensure that the tests pass when run under the profiler (which sends