[skip ci] Refine Has Collection Rate panel expression (#10303)

Signed-off-by: NEdward Zeng <jie.zeng@zilliz.com>

deployments/monitor/grafana/milvus-dashboard.json

@@ -531,14 +531,14 @@
       "steppedLine": false,
       "targets": [
         {
-          "expr": "sum(rate(milvus_rootcoord_create_collection_total{app_kubernetes_io_instance=~\"$instance\", app_kubernetes_io_name=\"$app_name\", namespace=\"$namespace\", type=\"total\"}[5m])) by (pod)",
+          "expr": "increase(milvus_rootcoord_create_collection_total{app_kubernetes_io_instance=~\"$instance\", app_kubernetes_io_name=\"$app_name\", namespace=\"$namespace\", type=\"total\"}[2m])/2",
           "interval": "",
           "legendFormat": "total",
           "queryType": "randomWalk",
           "refId": "A"
         },
         {
-          "expr": "sum(rate(milvus_rootcoord_create_collection_total{app_kubernetes_io_instance=~\"$instance\", app_kubernetes_io_name=\"$app_name\", namespace=\"$namespace\", type=\"success\"}[5m])) by (pod)",
+          "expr": "increase(milvus_rootcoord_create_collection_total{app_kubernetes_io_instance=~\"$instance\", app_kubernetes_io_name=\"$app_name\", namespace=\"$namespace\", type=\"success\"}[2m])/2",
           "interval": "",
           "legendFormat": "success",
           "refId": "B"
@@ -5879,4 +5879,4 @@
   "title": "Milvus2.0",
   "uid": "uLf5cJ3Gz",
   "version": 40
-}
\ No newline at end of file
+}