feat(firebase_ui_localizations): Add Finnish language localization labels

[launis]

Description

This PR adds new language Finnish. The translations are checked but not reviewed by third party.

The melos run analyze noticed error on the original main and these continued to be the same when I did with my changes,

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[russellwheatley]

Thanks for the PR! Could you also get a Finnish language speaker to also approve the PR and I will get this merged. Thanks 😄

[TimoPieti]

Looks mostly good as a Finnish speaking user. Just a couple of observations.

[jpsiitonen]

Checked latest changes to translations. LGTM

[TimoPieti]

LGTM for me too.

[launis]

Thanks for the PR! Could you also get a Finnish language speaker to also approve the PR and I will get this merged. Thanks 😄

Approved by two native Finnish speakers.

[launis]

Reopened, can be closed when code changes are merged to main.