Remove s3 prefix from report output bucket

#29

app/api/utils.py

@@ -134,7 +134,9 @@ async def start_workflow_execution(
         ctx = BinaryWriterContext(
             f,
             execution_id=execution.execution_id,
-            output_bucket=report_output_bucket,
+            output_bucket=report_output_bucket[5:]
+            if report_output_bucket is not None and report_output_bucket.startswith("s3://")
+            else report_output_bucket,
             parameters=json.dumps(parameters, indent=4),
         )
         config_template.render_context(ctx)