CSF: Expose story id in composeStories

[sjwilczynski]

What I did

In this PR we expose story id when using composeStory/composeStories. We do that to be able to identify a story when running unit tests. You can check https://github.com/microsoft/nova-facade/pull/72/files#diff-220d974cd0e74b45dc745889f0752372189a35d53bc122ac00ec3f52edf7063f to see what it can be used for. In this case we have a decorator which for each story saves something in module state. To be able to interact with that entity inside play function we need to be able to identify a story somehow and such identifier can be used as a key for that store (and relying on id instead of manually setting the storyName). To be honest my preferred solution would be to just add the information from decorator to parameters (in case of that PR, to set environment as another parameter from within decorator). But as discussed in #21252 (comment), it seems that changes to parameters are not visible in play function and I am not sure how long it would take for the behavior to be fixed. Therefore, this PR is a workaround but IMO also provides a nicer way to setup context for play function from within unit tests.

@yannbf, @tmeasday I am looking forward to hear your thoughts on this!

How to test

Check the added unit tests, to see the exposed ids.

Checklist

• Make sure your changes are tested (stories and/or unit, integration, or end-to-end tests)
• Make sure to add/update documentation regarding your changes
• If you are deprecating/removing a feature, make sure to update
  MIGRATION.MD

Maintainers

• If this PR should be tested against many or all sandboxes,
  make sure to add the ci:merged or ci:daily GH label to it.
• Make sure this PR contains one of the labels below.

["cleanup", "BREAKING CHANGE", "feature request", "bug", "documentation", "maintenance", "dependencies", "other"]

[yannbf]

This looks great to me! Thank you for such detailed explanation of your use case 👍

[yannbf]

This looks great to me! Thank you for such detailed explanation of your use case 👍

[sjwilczynski]

@yannbf thanks for the feedback, please let me know in case there is any action item on me, to get the PR in. Otherwise looking forward to it being merged and released!