Fix left room membership change

[ganfra]

Content

Ensure the right message is used when leaving room, according to the current membership :

• when leaving room
• when cancelling knock
• when declining invite

Also add some tests to ensure the room.leave triggers the correct membership change.

Motivation and context

Fix regression from removing RoomPreview leave usage.
Because of this the message was always "Left room".

Screenshots / GIFs

No ui change.

Tests

• Step 1
• Step 2
• Step ...

Tested devices

• Physical
• Emulator
• OS version(s):

Checklist

• Changes have been tested on an Android device or Android emulator with API 24
• UI change has been tested on both light and dark themes
• Accessibility has been taken into account. See https://github.com/element-hq/element-x-android/blob/develop/CONTRIBUTING.md#accessibility
• Pull request is based on the develop branch
• Pull request title will be used in the release note, it clearly define what will change for the user
• Pull request includes screenshots or videos if containing UI changes
• You've made a self review of your PR

[github-actions]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 80.36%. Comparing base (5a2aeac) to head (2b87281).
Report is 1 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #4765      +/-   ##
===========================================
+ Coverage    80.33%   80.36%   +0.02%     
===========================================
  Files         2135     2135              
  Lines        56431    56434       +3     
  Branches      7067     7068       +1     
===========================================
+ Hits         45336    45352      +16     
+ Misses        8678     8665      -13     
  Partials      2417     2417              

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[bmarty]

LGTM, thanks!

[bmarty]

Maybe create a private fun to avoid all the code duplication for those 3 tests?