update to dpub a11y document

Hi All,

I am having some settings issues in GitHub. It looks like "unknown" loaded an update to the document, but it was really me. I am trying to juggle 2 different accounts on GitHub, and it is really maddening.

Feel free to edit https://github.com/w3c/dpub-accessibility/commit/04cb12284a6d671d4d4cbe71755829fafd002293

Thanks,
Tzviya

Tzviya Siegman
Digital Book Standards & Capabilities Lead
Wiley
201-748-6884
tsiegman@wiley.com<mailto:tsiegman@wiley.com>