Fix sample container is not populated with items (#459)

src/Explorer/DataSamples/ContainerSampleGenerator.test.ts

@@ -61,6 +61,7 @@ describe("ContainerSampleGenerator", () => {
     const database = {
       id: ko.observable(sampleDatabaseId),
       collections: ko.observableArray<ViewModels.Collection>([collection]),
+      loadCollections: () => {},
     } as ViewModels.Database;
     database.findCollectionWithId = () => collection;
 
@@ -109,6 +110,7 @@ describe("ContainerSampleGenerator", () => {
     const database = {
       id: ko.observable(sampleDatabaseId),
       collections: ko.observableArray<ViewModels.Collection>([collection]),
+      loadCollections: () => {},
     } as ViewModels.Database;
     database.findCollectionWithId = () => collection;
     collection.databaseId = database.id();

src/Explorer/DataSamples/ContainerSampleGenerator.ts

@@ -63,6 +63,7 @@ export class ContainerSampleGenerator {
     if (!database) {
       return undefined;
     }
+    await database.loadCollections();
     return database.findCollectionWithId(this.sampleDataFile.collectionId);
   }