metrics: fix grafana expr for `tikv_gc_compaction_filtered`
close tikv/tikv#13537
fix error grafana expr for `tikv_gc_compaction_filtered `
"steppedLine": false,
"targets": [
{
- "expr": "sum(rate(tikv_gc_compaction_filtered{k8s_cluster=\"$k8s_cluster\", tidb_cluster=\"$tidb_cluster\", instance=~\"$instance\"}[1m])) by {key_mode}",
+ "expr": "sum(rate(tikv_gc_compaction_filtered{k8s_cluster=\"$k8s_cluster\", tidb_cluster=\"$tidb_cluster\", instance=~\"$instance\"}[1m])) by (key_mode)",
"format": "time_series",
"instant": false,
"interval": "",
