update all examples to use standalone components

[markgoho]

of the many example specs, only a couple focus on testing standalone components

given the trend towards standalone being the default, it would be valuable to the community to see more examples of how Testing Library can be used with standalone components and what aspects of the test must change in response to making the component standalone

[markgoho]

@timdeschryver is there value in doing this do you think?

[timdeschryver]

Hey @markgoho I think it is very valuable!
Thanks for the PR as well.
I had some other stuff on my list but I'm planning to go over the issues/PR of Angular Testing Library later this week/next week.
Thanks in advance!