Revert "s/.done(/.then(/ since modern es6 track unhandled promise exceptions"

This reverts commit 09a8fec2

src/components/structures/auth/ForgotPassword.js

@@ -105,7 +105,7 @@ module.exports = createReactClass({
             phase: PHASE_SENDING_EMAIL,
         });
         this.reset = new PasswordReset(this.props.serverConfig.hsUrl, this.props.serverConfig.isUrl);
-        this.reset.resetPassword(email, password).then(() => {
+        this.reset.resetPassword(email, password).done(() => {
             this.setState({
                 phase: PHASE_EMAIL_SENT,
             });