defer closing tailable file via subcontext

+ update deps for defer f.Close()

cmd/submit.go

@@ -117,8 +117,10 @@ func (s *submitter) shipFileRoutine(ctx context.Context, name string, deleteOk f
 	}
 	startSize := fi.Size()
 
-	// TODO: use inotify for file, and end with file deletion or replacement
-	lineChan, errChan, err := util.TailFile(ctx, name, log.Offset, io.SeekStart)
+	sctx, cancel := context.WithCancel(ctx)
+	defer cancel()
+
+	lineChan, errChan, err := util.TailFile(sctx, name, log.Offset, io.SeekStart)
 	if err != nil {
 		return fmt.Errorf("tailing file: %w", err)
 	}