title: json_extract_path_text does not unescape string values?
body: <p>When I run this query in Redshift, I would expect <code>json_extract_path_text</code> to remove the backslash from the <code>&quot;\&quot;b\&quot;&quot;</code> value:</p>
  <pre class="lang-sql prettyprint-override"><code>select j, json_extract_path_text(j, 'a', true) as a
  from (select '{&quot;a&quot;: &quot;\\&quot;b\\&quot;&quot;}' as j);
  </code></pre>
  <p>Instead, it appears that the string value is extracted verbatim, and the results look like this:</p>
  <pre><code>{&quot;a&quot;: &quot;\&quot;b\&quot;&quot;}
  \&quot;b\&quot;
  </code></pre>
  <p>Is this intentional? If yes, what would be the idiomatic way to remove the backslashes?</p>