spec: json-generator-read: object key must be a string.

Author: Amirouche

srfi-180.html

@@ -149,7 +149,7 @@ <h4 id="example-two">Example Two</h4>
 (cons &#39;json-value <span class="st">&quot;hello&quot;</span>)
 (cons &#39;json-value <span class="st">&quot;world&quot;</span>)
 (cons &#39;json-structure &#39;object-start)
-(cons &#39;json-value &#39;truth)
+(cons &#39;json-value <span class="st">&quot;truth&quot;</span>)
 (cons &#39;json-structure &#39;array-start)
 (cons &#39;json-value <span class="dv">42</span>)
 (cons &#39;json-structure &#39;array-end)