feat(run-virtual-rule): new api to run rules using only virtual nodes

[straker]

This api allows a user to run a rule without needing an actual DOM node. It completes the api needed to run a rule in a linter on individual virtual nodes.

const vNode = {
  shadowId: undefined,
  children: [],
  parent: undefined,
  _cache: {},
  _isHidden: null,
  _attrs: {
    type: 'text',
    autocomplete: 'not-on-my-watch',
  },
  props: {
    nodeType: 1,
    nodeName: 'input',
    id: null,
    type: 'text'
  },
  hasClass() {
    return false;
  },
  attr(attrName) {
    return this._attrs[attrName];
  },
  hasAttr(attrName) {
    return !!this._attrs[attrName];
  }
};

const results = axe.runVirtualRule('autocomplete-valid', vNode);

Linked issue: #1601

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• Follows the commit message policy, appropriate for next version
• Has documentation updated, a DU ticket, or requires no documentation change
• Includes new tests, or was unnecessary
• Code is reviewed for security by: @WilcoFiers

Resolved

[WilcoFiers]

Very minor point

Resolved