EntityStore: support filtering by labels (#59905)

* label filtering

* filtering in sql

* filtering in sql group by

* label is unique - no need for distinct

* capitalize

* fix capitalization

pkg/services/store/entity/tests/testdata/dashboard-with-tags-b-g.json

@@ -0,0 +1,40 @@
+{
+  "tags": [
+    "blue",
+    "green"
+  ],
+  "editable": true,
+  "fiscalYearStartMonth": 0,
+  "graphTooltip": 0,
+  "id": 221,
+  "links": [],
+  "liveNow": false,
+  "panels": [
+    {
+      "gridPos": {
+        "h": 1,
+        "w": 24,
+        "x": 0,
+        "y": 8
+      },
+      "id": 8,
+      "title": "Row title",
+      "type": "row"
+    }
+  ],
+  "schemaVersion": 36,
+  "style": "dark",
+  "templating": {
+    "list": []
+  },
+  "time": {
+    "from": "now-6h",
+    "to": "now"
+  },
+  "timepicker": {},
+  "timezone": "",
+  "title": "special ds",
+  "uid": "mocpwtR4k",
+  "version": 1,
+  "weekStart": ""
+}

pkg/services/store/entity/tests/testdata/dashboard-with-tags-r-g.json

@@ -0,0 +1,40 @@
+{
+  "tags": [
+    "red",
+    "green"
+  ],
+  "editable": true,
+  "fiscalYearStartMonth": 0,
+  "graphTooltip": 0,
+  "id": 221,
+  "links": [],
+  "liveNow": false,
+  "panels": [
+    {
+      "gridPos": {
+        "h": 1,
+        "w": 24,
+        "x": 0,
+        "y": 8
+      },
+      "id": 8,
+      "title": "Row title",
+      "type": "row"
+    }
+  ],
+  "schemaVersion": 36,
+  "style": "dark",
+  "templating": {
+    "list": []
+  },
+  "time": {
+    "from": "now-6h",
+    "to": "now"
+  },
+  "timepicker": {},
+  "timezone": "",
+  "title": "special ds",
+  "uid": "mocpwtR4k",
+  "version": 1,
+  "weekStart": ""
+}