Fixed typo in docs/ref/templates/builtins.txt.

docs/ref/templates/builtins.txt

@@ -1643,7 +1643,7 @@ For example::
 
     {{ value|escapejs }}
 
-If ``value`` is ``"testing\r\njavascript \'string" <b>escaping</b>"``,
+If ``value`` is ``"testing\r\njavascript 'string\" <b>escaping</b>"``,
 the output will be ``"testing\\u000D\\u000Ajavascript \\u0027string\\u0022 \\u003Cb\\u003Eescaping\\u003C/b\\u003E"``.
 
 .. templatefilter:: filesizeformat