[sitecore-jss-angular] fix placeholder guards

[spike1292]

When we upgraded to the angular 15 version we experienced the following issues:

1. Injectable placeholder guards where missing there this context
2. Guards could not navigate to a route anymore

• This PR follows the Contribution Guide
• Changelog updated

Description / Motivation

• Fixed problem 1. With changing guard.canActivate to guard.canActivate.bind(guard)
• Fixed problem 2. With a custom error JssCanActivateError
• Added a integration test to make sure the next upgrade does not break lazy loading, guards and routing features.
• Changed behaviour with lazy loaded placeholder components. Instead of throwing a uncatchable error we now expose the error through an event and a console.warn
  • if needed can be an other pr
  • this enables to gracefully handle an placeholder error. We want to be able to show an nice error to the customer instead of a empty placeholder.
• Add a lazy load helper to reduce boilerplate for lazy loaded components in modules.

Testing Details

• Unit Test Added
• Manual Test/Other
  • created a build, ran npm pack, included tar in our application. saw previous behaviour restored

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

[illiakovalenko]

@spike1292 Thank you for your valuable contribution. Your changes have been incorporated (pulled) into a separate Pull Request to allow for additional modifications before merging. We greatly appreciate your efforts!
I close this PR