Fixed widget template rendering issue while rewriting widget block

Author: sanganinamrata

app/code/Magento/CatalogWidget/etc/widget.xml

@@ -33,7 +33,7 @@
             <parameter name="template" xsi:type="select" required="true" visible="true">
                 <label translate="true">Template</label>
                 <options>
-                    <option name="default" value="product/widget/content/grid.phtml" selected="true">
+                    <option name="default" value="Magento_CatalogWidget::product/widget/content/grid.phtml" selected="true">
                         <label translate="true">Products Grid Template</label>
                     </option>
                 </options>

app/code/Magento/Widget/Test/Unit/Model/WidgetTest.php

@@ -174,7 +174,7 @@ public function testGetWidgetDeclaration()
             'show_pager' => '1',
             'products_per_page' => '5',
             'products_count' => '10',
-            'template' => 'product/widget/content/grid.phtml',
+            'template' => 'Magento_CatalogWidget::product/widget/content/grid.phtml',
             'conditions' => $conditions
         ];
 
@@ -187,7 +187,7 @@ public function testGetWidgetDeclaration()
                 ['1', false, '1'],
                 ['5', false, '5'],
                 ['10', false, '10'],
-                ['product/widget/content/grid.phtml', false, 'product/widget/content/grid.phtml'],
+                ['Magento_CatalogWidget::product/widget/content/grid.phtml', false, 'Magento_CatalogWidget::product/widget/content/grid.phtml'],
                 ['encoded-conditions-string', false, 'encoded-conditions-string'],
             ]);
 
@@ -225,7 +225,7 @@ public function testGetWidgetDeclarationWithZeroValueParam()
             'show_pager' => '1',
             'products_per_page' => '5',
             'products_count' => '0',
-            'template' => 'product/widget/content/grid.phtml',
+            'template' => 'Magento_CatalogWidget::product/widget/content/grid.phtml',
             'conditions' => $conditions
         ];