Remove unused TagSoup proguard rule

[jmartinesp]

Content

Remove this rule, which doesn't really do anything anymore AFAICT.

Motivation and context

Does as much of #5705 as we can.

Tests

Build the app in release mode, it should keep working as expected.

Tested devices

• Physical
• Emulator
• OS version(s): 15

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 79.61%. Comparing base (516fc72) to head (f787eb2).
⚠️ Report is 94 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #5707      +/-   ##
===========================================
- Coverage    79.65%   79.61%   -0.05%     
===========================================
  Files         2427     2427              
  Lines        65212    65212              
  Branches      8318     8318              
===========================================
- Hits         51945    51917      -28     
- Misses       10291    10318      +27     
- Partials      2976     2977       +1     

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[jmartinesp]

• Coverage 79.65% 79.61% -0.05%

Huh, I guess it wasn't that unused then 👀