fix: Use native unicode emojis [WPB-5790] (#16331)

[atomrc]

WPB-5790 [Web] Replace emojis in the reaction picker and in the reaction with pure UTF-8 characters

Description

backport of #16331 for master branch

Checklist

• PR has been self reviewed by the author;
• Hard-to-understand areas of the code have been commented;
• If it is a core feature, unit tests have been added;

[codecov]

Codecov Report

Merging #16333 (f7a1116) into master (9684e05) will increase coverage by 0.00%.
The diff coverage is 100.00%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #16333   +/-   ##
=======================================
  Coverage   44.49%   44.49%           
=======================================
  Files         674      674           
  Lines       22755    22752    -3     
  Branches     5174     5175    +1     
=======================================
- Hits        10125    10124    -1     
+ Misses      11337    11335    -2     
  Partials     1293     1293