feat: ability to specify if selfClosing element is a void element

[gastonyte]

Summary

That PR is about adding ability for users to not add a / at the end of specific void elements (like <br>, <link> or <input> elements)

This change originally come from https://github.com/apostrophecms/sanitize-html/issues/51

What are the specific steps to test this change?

type SelfClosingOptions = Record<string, boolean | { voidElement: boolean }>

type MyIOptions = Omit<sanitizeHtml.IOptions, 'selfClosing'> & {
  selfClosing?: SelfClosingOptions | string[] | undefined
}

const sanitizationOptions: MyIOptions = {
  allowedTags: ['p', 'strong', 'em', 'u', 's', 'blockquote', 'ul', 'ol', 'li', 'br'],
  allowedAttributes: {},
  selfClosing: {
    br: {
      voidElement: true
    }
  },
}

const cleaned = sanitizeHtml(
  value,
  sanitizationOptions as sanitizeHtml.IOptions
)

What kind of change does this PR introduce?

(Check at least one)

• [ ] Bug fix
• [x] New feature
• [ ] Refactor
• [ ] Documentation
• [ ] Build-related changes
• [ ] Other

Make sure the PR fulfills these requirements:

• [ ] It includes a) the existing issue ID being resolved, b) a convincing reason for adding this feature, or c) a clear description of the bug it resolves
• [ ] The changelog is updated
• [ ] Related documentation has been updated
• [x] Related tests have been updated

If adding a new feature without an already open issue, it's best to open a feature request issue first and wait for approval before working on it.

Other information:

[gastonyte]

I didn't change the documentation because I don't know where to write about voidElement because the section explaining selfClosing does not exist yet.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[BoDonkey]

Bump to remove label.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[BoDonkey]

I know this has been a long back and forth, but do you know if you will be able to finish this @gastonyte?