Call for review: Adjust meta viewport applicability based on properties defined

Hey folks,

This pull request tweaks the applicability so that fewer meta elements are
considered applicable. Essentially making a few things that passed before
inapplicable. If you have any comments, please leave a review by June 23rd:
https://github.com/act-rules/act-rules.github.io/pull/1835/files

Kind regards,

-- 
*Wilco Fiers*
Axe-core & Axe-linter product owner - WCAG 3 Project Manager - Facilitator
ACT Task Force