Remove obsolete slusters config section

internal/repository/node_test.go

@@ -38,18 +38,7 @@ func nodeTestSetup(t *testing.T) {
   "jwts": {
       "max-age": "2m"
   }
-	},
-	"clusters": [
-	{
-	   "name": "testcluster",
-	   "metricDataRepository": {"kind": "test", "url": "bla:8081"},
-	   "filterRanges": {
-		"numNodes": { "from": 1, "to": 64 },
-		"duration": { "from": 0, "to": 86400 },
-		"startTime": { "from": "2022-01-01T00:00:00Z", "to": null }
-	   }
 	}
-	]
 }`
 	const testclusterJSON = `{
         "name": "testcluster",