fix VectorCustomServerDialog props

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

src/components/views/auth/VectorCustomServerDialog.js

@@ -22,7 +22,7 @@ import { _t } from 'matrix-react-sdk/lib/languageHandler';
  * This is identical to `CustomServerDialog` except for replacing "this app"
  * with "Riot".
  */
-module.exports = () => {
+module.exports = ({onFinished}) => {
     return (
         <div className="mx_ErrorDialog">
             <div className="mx_Dialog_title">
@@ -42,7 +42,7 @@ module.exports = () => {
                 )}</p>
             </div>
             <div className="mx_Dialog_buttons">
-                <button onClick={this.props.onFinished} autoFocus={true}>
+                <button onClick={onFinished} autoFocus={true}>
                     { _t('Dismiss') }
                 </button>
             </div>