message: fix typo in state sync metric
  Closes:
  Approved by: sunmilee
diff: "steppedLine": false,
  "targets": [
  {
  - "expr": "libra_state_sync_timeout",
  + "expr": "libra_state_sync_timeout_total",
  "format": "time_series",
  "intervalFactor": 1,
  "legendFormat": "{{peer_id}}",
  