RuleID 5f99a7 - map to 4.1.2 - ARIA attribute is defined in WAI-ARIA

[philljenkins]

ACT should not suppport rules that don't map to WCAG Success Criteria (e.g. none)
When tools report implementations, reporting against "none" too often will/has diluted the effectiveness of the rules, its reputation, and more importantly credibility and understanding of the accessibility requirements. Even recommendations by the tool should map to a success critera topic.

4.1.2 was designed to be used to report against custom ARIA widgets where attribute values are defined incorrectly. If ARIA is not defined correctly, then assistive technology can have determintal effects for users.
Success Criteria 4.1.2 about programmatically determined; states, properties, and values.

Proposed
RuleID 5f99a7
ARIA attribute is defined in WAI-ARIA
https://wai-wcag-act-rules.netlify.app/standards-guidelines/act/rules/5f99a7/proposed

• ACT should report 4.1.2 (vs none)
  

[WilcoFiers]

See my comment #137 (comment)