Generate a nonce per request, for example:
NzEyOTc4NjgxLDMyNjI0MTk1ODA=
Include the nonce in your strict CSP:
Content-Security-Policy: script-src 'nonce-NzEyOTc4NjgxLDMyNjI0MTk1ODA='
Add the nonce attribute to your AddToAny <script> tag like so:
<script async nonce="NzEyOTc4NjgxLDMyNjI0MTk1ODA=" src="https://static.addtoany.com/menu/page.js"></script>