Incorrect error reported for ARIA role "separator" on images

[gregoriopellegrino]

Please provide the following details if possible or relevant:

• [] the version of Ace impacted by the issue (as returned by the ace -v command): 1.3.2
• [] the version of Node used to run Ace (as returned by the node -v command): v18.16.1
• [] your operating system and version: macOS 14.3.1

Ace by DAISY currently flags the usage of the ARIA role separator on images as an error with the message aria-allowed-role. However, according to the HTML ARIA specification, the role separator is valid for images.

Steps to Reproduce:

• Insert an image element in the EPUB with the ARIA role separator, e.g., <img src="../Images/separator.png" role="separator" />
• Run Ace by DAISY or use the tool to check for accessibility errors

Expected Behavior: Ace by DAISY should recognize the ARIA role separator on images as valid and not flag it as an error.