[Rich text editor] Fix placeholder spilling onto multiple lines

[jonnyandrew]

Type of change

• Feature
• Bugfix
• Technical
• Other :

Content

Fix rich text editor placeholder spilling onto multiple lines.

Motivation and context

The French translation for the editor placeholder is verbose and may spill onto multiple lines if not truncated.

Screenshots / GIFs

Tests

Tested manually by substituting the placeholder with long text.

Tested devices

• Physical
• Emulator
• OS version(s): Android 13

Checklist

• Changes have been tested on an Android device or Android emulator with API 23
• UI change has been tested on both light and dark themes
• Accessibility has been taken into account. See https://github.com/vector-im/element-x-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-x-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

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[codecov]

Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (6563dca) 57.91% compared to head (0b71881) 57.92%.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #1347   +/-   ##
========================================
  Coverage    57.91%   57.92%           
========================================
  Files         1109     1109           
  Lines        29256    29258    +2     
  Branches      5976     5976           
========================================
+ Hits         16945    16947    +2     
  Misses        9683     9683           
  Partials      2628     2628           

Files Changed	Coverage Δ
...ent/android/libraries/textcomposer/TextComposer.kt	54.71% <100.00%> (+0.24%)	⬆️

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[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information

[bmarty]

Thanks!