fixes #4849 - minor fix for metric-segment-model (agg.field)

public/app/plugins/datasource/elasticsearch/partials/bucket_agg.html

@@ -6,7 +6,7 @@
 		</label>
 
 		<metric-segment-model property="agg.type" options="bucketAggTypes" on-change="onTypeChanged()" custom="false" css-class="width-10"></metric-segment-model>
-		<metric-segment-model ng-if="agg.field" property="agg.field" get-options="getFieldsInternal()" on-change="onChange()" css-class="width-12"></metric-segment>
+		<metric-segment-model ng-if="agg.field" property="agg.field" get-options="getFieldsInternal()" on-change="onChange()" css-class="width-12"></metric-segment-model>
 	</div>
 
 	<div class="gf-form gf-form--grow">