docs: fix error syntax (#42824)

Co-authored-by: Ali <ali.wu@miotech.com>

components/form/demo/register.tsx

@@ -176,7 +176,7 @@ const App: React.FC = () => {
               if (!value || getFieldValue('password') === value) {
                 return Promise.resolve();
               }
-              return Promise.reject(new Error('The two passwords that you entered do not match!'));
+              return Promise.reject(new Error('The new password that you entered do not match!'));
             },
           }),
         ]}