Updated the Route Guard for Angular (#3731)

* Update 104-guards.md

Added the link for resolve route guard

* Update 103-router-events.md

Added the documentation for Router events.

---------

Co-authored-by: Kamran Ahmed <kamranahmed.se@gmail.com>

src/data/roadmaps/angular/content/107-routing/103-router-events.md

@@ -1 +1,5 @@
-# Router events
+# Router Events
+
+The Angular Router raises events when it navigates from one route to another route. It raises several events such as `NavigationStart`, `NavigationEnd`, `NavigationCancel`, `NavigationError`, `ResolveStart`, etc. You can listen to these events and find out when the state of the route changes. Some of the useful events are route change start (NavigationStart) and route change end (NavigationEnd).
+
+- [Angular Official Website](https://angular.io/api/router/RouterEvent)

src/data/roadmaps/angular/content/107-routing/104-guards.md

@@ -12,3 +12,4 @@ Visit the following resources to learn more:
 - [Can Deactivate](https://angular.io/api/router/CanDeactivate)
 - [Angular Can Load](https://angular.io/api/router/CanLoad)
 - [Can Match](https://angular.io/api/router/CanMatch)
+- [Resolve](https://angular.io/api/router/Resolve)