docs: add ngx-http-request-state (#973)

README.md

@@ -615,6 +615,7 @@ become an Angular expert.
 * [ngx-http-retry](https://github.com/itpixelz/ngx-http-retry) - An Angular service that provides HTTP methods (GET, POST, PUT, DELETE) with built-in retry logic using RxJS's `retry` operator.
 * [ng-memento](https://github.com/terzurumluoglu/ng-memento) - Makes your application faster by preventing the same HTTP requests from being called again in your Angular project.
 * [ngx-suspense-of](https://github.com/Celtian/ngx-suspense-of) - Angular directive that adds suspense to your app.
+* [ngx-http-request-state](https://github.com/daiscog/ngx-http-request-state) - An Angular library for wrapping HttpClient responses with loading & error information.
 
 #### Integrations