Fix: Removing american Zs

[JT-39]

Pull request overview

There are some words which have the American spelling of using a "z" instead of a "s".

Pull request checklist

Please check if your PR fulfills the following:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)
• Tests have been run locally and are passing (shinytest2::test_app())
• Code is styled according to tidyverse styling (checked locally with styler::style_dir() and lintr::lint_dir())

What is the current behaviour?

See overview.

What is the new behaviour?

All "z" changed to "s".

Anything else

May be others to watch out for.

[ArthurMurrell]

Checked on Tuesday. so just approving now.