fix generic

Author: aburmeis

src/test/java/com/arangodb/springframework/core/template/ArangoTemplateTest.java

@@ -410,7 +410,7 @@ public void deleteDocuments() {
 		final Product documentA = template.find(a.getId(), Product.class).get();
 		final Product documentB = template.find(b.getId(), Product.class).get();
 
-		final MultiDocumentEntity<DocumentDeleteEntity<?>> res = template.deleteAll(Arrays.asList(documentA, documentB), Product.class);
+		final MultiDocumentEntity<DocumentDeleteEntity<Product>> res = template.deleteAll(Arrays.asList(documentA, documentB), Product.class);
 		assertThat(res, is(notNullValue()));
 		assertThat(res.getDocuments().size(), is(2));