GUACAMOLE-103: Remove unnecessary parameter decoding

extensions/guacamole-auth-saml/src/main/java/org/apache/guacamole/auth/saml/AuthenticationProviderService.java

@@ -100,7 +100,7 @@ public class AuthenticationProviderService {
         if (request != null) {
             
             // Look for the SAML Response parameter.
-            String responseHash = Util.urlDecoder(request.getParameter("responseHash"));
+            String responseHash = request.getParameter("responseHash");
 
             if (responseHash != null) {