Update Grafana files

Author: ebattat

benchmark_runner/grafana/perf/dashboard.json

@@ -2126,6 +2126,10 @@
                            "index": 518,
                            "text": "4.20.6"
                         },
+                        "4207": {
+                           "index": 547,
+                           "text": "4.20.7"
+                        },
                         "4210": {
                            "index": 535,
                            "text": "4.21.0"