fix(angular): prevent memory leak when the root view is removed

[arturovt]

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The TraceService creates multiple subscriptions to router.events and never unsubscribes. The root view may be created and destroyed many times in different cases:

• micro-frontend app (the AppModule is bootstrapped and destroyed through NgModuleRef.destroy() whenever the app should be rendered or destroyed)
• server-side rendering

In the above cases, this keeps creating the TraceService for each new app, but it also prevents many resources from being GC'd, for instance TraceService, AppModule (since its injector keeps the reference), Router, etc.

[kamilogorek]

Makes perfect sense. Thanks!

[kamilogorek]

Whoops, wrong button.

[kamilogorek]

2 small linter issues, otherwise approved.