just use os

Author: ychin

.github/actions/test_artifacts/action.yml

@@ -35,7 +35,7 @@ runs:
           github.run_attempt,
           github.job,
           strategy.job-index,
-          steps.matrix-props.outputs.result) }}
+          inputs.os) }}
 
         # A file, directory or wildcard pattern that describes what
         # to upload.