Make blob upload progress heartbeat unambiguous (vs snapshot progress)

internal/snapshot/scanner.go

@@ -1236,7 +1236,7 @@ func (s *Scanner) makeUploadProgressCallback(ctx context.Context, finishedBlob *
 			if avgSpeed > 0 {
 				eta = time.Duration(float64(finishedBlob.Compressed-uploaded)/avgSpeed) * time.Second
 			}
-			_, _ = fmt.Fprintf(s.output, "  uploading %s: %s/%s (%.0f%%), %s/sec, %s elapsed, ETA %s\n",
+			_, _ = fmt.Fprintf(s.output, "  blob upload %s: %s/%s (%.0f%%) at %s/sec, blob upload elapsed %s, blob upload ETA %s\n",
 				finishedBlob.Hash[:12]+"...",
 				humanize.Bytes(uint64(uploaded)),
 				humanize.Bytes(uint64(finishedBlob.Compressed)),