Hello @cathysarisky

Ref #23361

If possible, I'd very much appreciate if you can label this PR with hacktoberfest-accepted 🙏

This translates missing strings into Finnish.
A few minor changes were made to previously submitted translations to fix typos or formatting:

comments.json
"Add context to your comment, share your name and expertise to foster a healthy discussion.": "Lisää sisältöä kommenttiisi, jaa nimesi ja osaamisesi saadaksesi aikaan tervettä keskustelua.",
"Become a member of {publication} to start commenting.": "Ala {publication} jäseneksi pystyäksesi kommentoimaan.",
"Become a paid member of {publication} to start commenting.": "Ota maksullinen jäsenyys sivulle {publication}, jotta pystyt kommentoimaan.",
"This comment has been hidden.": "Tämä kommentti on piilotettu.",
"This comment has been removed.": "Tämä kommentti on poistettu.",
"Your request will be sent to the owner of this site.": "Sinun pyyntösi lähetetään sivun omistajalle."
--> missed fullstops at the end

ghost.json
"If you did not make this request, you can safely ignore this email.": "Jos et tehnyt tätä pyyntöä, voit olla reagoimatta viestiin.",
--> typo 'tehny' corrected to 'tehnyt', missed fullstop at the end

"If you did not make this request, you can simply delete this message.": "Jos et tehnyt tätä pyyntöä, voit poistaa tämän viestin.",
--> missed fullstop at the end

"Thank you for subscribing to {siteTitle}. Tap the link below to be automatically signed in:": "Kiitos tilauksestasi sivulle {siteTitle}. Klikkaa alla olevaa linkkiä jatkaaksesi.",
--> "Kiitos tilauksestasi sivulle" was duplicated

portal.json
"After a free trial ends, you will be charged the regular price for the tier you've chosen. You can always cancel before then.": "Kun ilmainen kokeilusi loppuu, sinulta veloitetaan valitsemasi tilauksen maksu. Voit aina peruuttaa tilauksesi ennen tätä.",
--> previously specified 'kuukausimaksu' but I believe it's not always a monthly payment but perhaps e.g. yearly

"Complimentary": "Maksuton",
--> used to be "Ilmainen" but had to make a distinction between free and complimentary

"Plan checkout was cancelled.": "Tilauksen maksaminen on peruttu",
--> checkout was left untranslated but there's no need for that

"Re-enable emails": "Hyväksy sähköpostit uudelleen",
--> used to be "Uudelleen hyväksy" but that's not proper grammar

"Renews at {price}.": "Tilaus uusiutuu hinnalla {price}.",
--> used to be "päivittyy" but the previous translator had elsewhere used 'uusiutuu' so I made it consistent

"There was a problem submitting your feedback. Please try again a little later.": "Meillä oli ongelma palautteesi lähetyksen kanssa. Kokeilethan myöhemmin uudestaan.",
--> There was a typo 'kokeleithan'

"When an inbox fails to accept an email it is commonly called a bounce. In many cases, this can be temporary. However, in some cases, a bounced email can be returned as a permanent failure when an email address is invalid or non-existent.": "Jos sähköpostilaatikko ei pysty vastaanottamaan viestiä, sitä kutsutaan “bounssaamiseksi”. Usein se on väliaikaista. Joissakin tapauksissa “bounssannut” sähköposti voi kuitenkin palautua pysyvänä virheenä, kun sähköpostiosoite on virheellinen tai sitä ei ole olemassa.",
--> A big chunk of text had disappeared from the beginning.

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