[MM-58008] Calls Mobile: Settings for DM/GM ringing (#27213)

* prevent webapp from erasing new mobile notify props

* allow blank, will be used on mobile to default to desktop setting

* update snapshots

* Revert "update snapshots"

This reverts commit 0bcd515de87e2e3fdd8a87e73f52c845577eddab.

* Revert "allow blank, will be used on mobile to default to desktop setting"

This reverts commit 56e16e887ff7bfbf3751778cc31cdd9e0e0f8086.

* Revert "prevent webapp from erasing new mobile notify props"

This reverts commit e983d7b8f4dbd92b12eeb312cdf64ec45cd2d6ec.

* simplify how we handle mobile notification props

* linting

---------

Co-authored-by: Mattermost Build <build@mattermost.com>

webapp/channels/src/components/user_settings/notifications/user_settings_notifications.tsx

@@ -231,7 +231,7 @@ class NotificationsTab extends React.PureComponent<Props, State> {
     }
 
     handleSubmit = async () => {
-        const data: UserNotifyProps = {} as UserNotifyProps;
+        const data: UserNotifyProps = {...this.props.user.notify_props};
         data.email = this.state.enableEmail;
         data.desktop_sound = this.state.desktopSound;
         data.calls_desktop_sound = this.state.callsDesktopSound;