Update spec/index.html

Author: pchampin

spec/index.html

@@ -768,7 +768,7 @@ <h3>Literals</h3>
         language tag MUST be well-formed according to
         <a data-cite="bcp47#section-2.2.9">section 2.2.9</a>
         of [[!BCP47]],
-        and MUST be treated consistently, that is, in a case insensitive manner.
+        and MUST be treated accordingly, that is, in a case insensitive manner.
         Two [[!BCP47]]-complying strings that differ only by case represent the same [=language tag=].</li>
       <li>If and only if the <a>datatype IRI</a> is
         <code>http://www.w3.org/1999/02/22-rdf-syntax-ns#dirLangString</code>,