textops: fix broken example for filter_body

(cherry picked from commit f8c1cabaeadb8ee145174843ed11bbbb0c3276b0)

src/modules/textops/doc/textops_admin.xml

@@ -859,7 +859,7 @@ set_reply_body("test", "text/plain");
 		<programlisting format="linespecific">
 ...
 if (has_body("multipart/mixed")) {
-    if (filter_body("application/sdp") {
+    if (filter_body("application/sdp")) {
         remove_hf("Content-Type");
         append_hf("Content-Type: application/sdp\r\n");
     } else {