[Notification mode] Wrong mode is displayed when the mention only is selected on the web client

[Claire1817]

Type of change

• Feature
• Bugfix
• Technical
• Other :

Content

Motivation and context

Use none in android application when all messages or mentions only is selected in the web application.
tchapgouv/tchap-android#464

Screenshots / GIFs

Android:

Web:

Tests

• Update Notification settings in web application to mention only
• Check if in Android application the notifications preference is equal to None.

Tested devices

• Physical
• Emulator
• OS version(s):

Checklist

• Changes has been tested on an Android device or Android emulator with API 21
• UI change has been tested on both light and dark themes
• Accessibility has been taken into account. See https://github.com/vector-im/element-android/blob/develop/CONTRIBUTING.md#accessibility
• Pull request is based on the develop branch
• Pull request includes a new file under ./changelog.d. See https://github.com/vector-im/element-android/blob/develop/CONTRIBUTING.md#changelog
• Pull request includes screenshots or videos if containing UI changes
• Pull request includes a sign off
• You've made a self review of your PR
• If you have modified the screen flow, or added new screens to the application, you have updated the test UiAllScreensSanityTest.allScreensTest()

[github-actions]

Unit Test Results

102 files  +  4  102 suites  +4   1m 5s ⏱️ -5s
182 tests +  3  182 ✔️ +  3  0 💤 ±0  0 ❌ ±0 
598 runs  +10  598 ✔️ +10  0 💤 ±0  0 ❌ ±0 

Results for commit b073724. ± Comparison against base commit 30c325b.

♻️ This comment has been updated with latest results.

[fedrunov]

LGTM, thanks