Soome spelling stuff :)

[boehs]

Checklist

• [x] My branch is up-to-date with the upstream develop branch.
• [ ] I have added necessary documentation (if appropriate).

Why do we need this PR?:

To make readability better.

TODOs (if any):

• [ ] Additional proofreading for other text files

Note: Despite the TODO this PR can be merged :)