Allowed excluding certain elements from CSS reset

[oleq]

Suggested merge commit message (convention)

Feature (theme-lark): Implemented a .ck-reset_all-excluded CSS class that excludes certain elements from CSS reset. Closes #11451.

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Additional information

Demo in the manual test in the theme-lark package.

[oleq]

@ckeditor/qa-team Could you please check if this change does not break the UI of the editor? 🙏 The scope is vast, any piece of UI could be affected and there's no easy way to confirm that other than going through all guides/features (also in CF) 😬.

[dufipl]

@oleq
We have tested this branch on docs on Chrome, Firefox and Safari and it looks good. Also, it does not look like it is breaking CF manual tests or collaboration samples so it looks good for us 👍

[Reinmar]

TODO @oleq add a note about this PR being a breaking change.

[oleq]

TODO @oleq add a note about this PR being a breaking change.

False alert. I thought using .ck.ck-reset_all * won't be possible but the I realized .ck stays in DOM so we're good. Sorry for the confusion.

[Reinmar]

What about the border-collapse style? It seems that it somehow leaks from... something.

[Reinmar]

Oleq explained to me that ☝️ is a dev tools issue.

All looks good then :)