[css-ruby] Add issue wrt spacing out ruby contents in case of spanning annotations

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extra : rebase_source : d95e99bf960d55a157ed7dc16d5749cc8cc0f1cd
[css-ruby] Note that ruby distribution space and text justification space are not related.

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extra : rebase_source : 16b2ba21526fe5cc0b8e05f3dea798d017229c91