Use extracted MessageBuilder library

[JeroenDeDauw]

Use https://github.com/ProfessionalWiki/MessageBuilder instead of https://github.com/ProfessionalWiki/EDTF/tree/master/src/PackagePrivate/Humanizer/Internationalization

Note:

• This is not a breaking change since the moved (and renamspaced) classes where marked as PackagePrivate
• The MessageBuilderSpy from tests is also moved
• The TranslationsLoader/ files did not get moved
• The new lib requires PHP 8.1, so we can drop compat for PHP 8.0 and older in EDTF