More exercises

[seanmisra]

Pending exercises:

• Custom Decorator
• use Optional/Host for dependency injection
• UntypedFormGroups (Angular 14)
• Standalone components (Angular 14)
• Angular material example
• Pure/impure pipes
• turn on strict mode and resolve any compilation errors
• Integrate with GO rest API

Done:

• HTTPInteceptor (intercept request/response)
• singleton vs non-singleton service
• Lifecycle Hooks (demonstrate difference btw ngOnInit, ngAfterViewInit (view children) and ngAfterViewContent (view content)
• rxjs timer() vs setTimeout()