Fix transition to use correct translateY for vertical alignment

[pik]

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[pik]

I signed it!

[googlebot]

CLAs look good, thanks!

[valdrinkoshi]

@pik could you please create an issue and refer to it in this PR?

Regarding the change, it would be enough to only update the styles and not introduce an observer. WDYT?

Also, it would be great to have a unit test for this new feature 👌

[valdrinkoshi]

you could only add this new style, with a selector :host([vertical-align="top"])