* Set expected line height to an expanded GELS line on IRC layout, add a test
* Add a test for compact modern/group layout
* Create a new test category on timeline.spec.ts
* Rename the class name as 'spacer'
* Add a test for GELS' spacer on bubble layout
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Signed-off-by: Suguru Hirahara <luixxiul@users.noreply.github.com>
Co-authored-by: Germain <germain@souquet.com>