refs #20945 [de_105] w3c validation - syntax fixes

* urlEncode links for additional authors and subjects, also remove escaping
* use record view helper in data-authors.phtml and result-list.phtml
* use <a> instead of <div> as container for data-toggler in EbscoResults.phtml
* use <div> instead of <span> and set <noscript> within <form> in cart-buttons.phtml
* encode url in footer links
* use <button> instead of <a> for submit button in header
* remove aria-labelledby="modal-title" from layout.phtml

co-authored by: Robert Lange <robert.lange@uni-leipzig.de>
* urlEncode links for additional authors and subjects, also remove escaping