AzureMonitor: Fix missing top parameter when dimensions are set (#47010) (#47017)

(cherry picked from commit 48113beeeb)

Co-authored-by: Andres Martinez Gotor <andres.mgotor@gmail.com>

pkg/tsdb/azuremonitor/azuremonitor-datasource.go

@@ -126,7 +126,9 @@ func (e *AzureMonitorDatasource) buildQueries(queries []backend.DataQuery, dsInf
 
 		if dimSB.String() != "" {
 			params.Add("$filter", dimSB.String())
-			params.Add("top", azJSONModel.Top)
+			if azJSONModel.Top != "" {
+				params.Add("top", azJSONModel.Top)
+			}
 		}
 
 		target = params.Encode()

pkg/tsdb/azuremonitor/azuremonitor-datasource_test.go

@@ -114,6 +114,17 @@ func TestAzureMonitorBuildQueries(t *testing.T) {
 			expectedInterval:        "PT1M",
 			azureMonitorQueryTarget: "%24filter=blob+eq+%27%2A%27+and+tier+eq+%27%2A%27&aggregation=Average&api-version=2018-01-01&interval=PT1M&metricnames=Percentage+CPU&metricnamespace=Microsoft.Compute-virtualMachines&timespan=2018-03-15T13%3A00%3A00Z%2F2018-03-15T13%3A34%3A00Z&top=30",
 		},
+		{
+			name: "has a dimension filter without specifying a top",
+			azureMonitorVariedProperties: map[string]interface{}{
+				"timeGrain":       "PT1M",
+				"dimension":       "blob",
+				"dimensionFilter": "*",
+			},
+			queryInterval:           duration,
+			expectedInterval:        "PT1M",
+			azureMonitorQueryTarget: "%24filter=blob+eq+%27%2A%27&aggregation=Average&api-version=2018-01-01&interval=PT1M&metricnames=Percentage+CPU&metricnamespace=Microsoft.Compute-virtualMachines&timespan=2018-03-15T13%3A00%3A00Z%2F2018-03-15T13%3A34%3A00Z",
+		},
 	}
 
 	commonAzureModelProps := map[string]interface{}{