fix: fix observable

src/testing/http.ts

@@ -0,0 +1,9 @@
+import { HttpFeatureKind } from '@ngify/http';
+import { HttpClientTestingBackend } from '@ngify/http/testing';
+
+export function provideHttpClientTesting() {
+  return {
+    provide: HttpFeatureKind.Backend,
+    useClass: HttpClientTestingBackend,
+  };
+}

src/testing/index.ts

@@ -6,3 +6,4 @@ export {
 } from './spy';
 export { createRetriableStream } from './create-retriable-stream.helper';
 export { MockRouter, mockRouterProvider } from './router';
+export { provideHttpClientTesting } from './http';