fix: set emoji image draggable attribute to false (WPB-4775)

[V-Gira]

WPB-4775 Drag and drop sends a message immediately without confirmation

Description

Emoji pill's image could get dragged, dropped and sent as a new message by accident on certain OSs
Setting the html attribute draggable to false prevents that issue

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 #15856 (ff03392) into dev (4845430) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##              dev   #15856   +/-   ##
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  Coverage   44.51%   44.51%           
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  Files         673      673           
  Lines       22733    22733           
  Branches     5168     5168           
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  Hits        10120    10120           
  Misses      11321    11321           
  Partials     1292     1292