chore(cascading combos): fix sample height

Author: katherinedragieva

src/app/grid/grid-cascading-combos/grid-cascading-combos.component.html

@@ -1,7 +1,7 @@
 <div class="grid__wrapper">
     <div class="sample__header">
         <igx-grid [igxPreventDocumentScroll]="true" #grid1 [data]="data" [autoGenerate]="false" displayDensity="cosy"
-            width="100%" height="600px" [primaryKey]="'ID'">
+            width="100%" height="500px" [primaryKey]="'ID'">
             <igx-column field="ID" header="ID" [dataType]="'number'" width="50px">
             </igx-column>
             <igx-column field="Country" header="Country" [dataType]="'string'" width="220px">