chore: add a grafana dashboard tag name for filter (#11441)

diff --git a/docs/en/setup/backend/grafana-cluster.json b/docs/en/setup/backend/grafana-cluster.json
index ba99a90..6235427 100644
--- a/docs/en/setup/backend/grafana-cluster.json
+++ b/docs/en/setup/backend/grafana-cluster.json
@@ -4373,7 +4373,9 @@
   "refresh": false,
   "schemaVersion": 21,
   "style": "dark",
-  "tags": [],
+  "tags": [
+    "skywalking"
+  ],
   "templating": {
     "list": [
       {
diff --git a/docs/en/setup/backend/grafana-instance.json b/docs/en/setup/backend/grafana-instance.json
index 874595a..c39217f 100644
--- a/docs/en/setup/backend/grafana-instance.json
+++ b/docs/en/setup/backend/grafana-instance.json
@@ -4964,7 +4964,9 @@
   "refresh": "",
   "schemaVersion": 21,
   "style": "dark",
-  "tags": [],
+  "tags": [
+    "skywalking"
+  ],
   "templating": {
     "list": [
       {