chore: Remove polyfills out of our support range

[tassoevan]

Proposed changes (including videos or screenshots)

It removes browser polyfills that are no longer necessary (given our browser support).

Issue(s)

ARCH-1714

Steps to test or reproduce

Further comments

[dionisio-bot]

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[changeset-bot]

⚠️ No Changeset found

Latest commit: 8f0f437

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[github-actions]

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🚀 View preview at https://RocketChat.github.io/Rocket.Chat/pr-preview/pr-36428/
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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 65.61%. Comparing base (0d45149) to head (8f0f437).
Report is 6 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #36428      +/-   ##
===========================================
+ Coverage    65.58%   65.61%   +0.03%     
===========================================
  Files         3172     3168       -4     
  Lines       105484   105404      -80     
  Branches     20043    20034       -9     
===========================================
- Hits         69179    69164      -15     
+ Misses       33630    33560      -70     
- Partials      2675     2680       +5     

Flag	Coverage Δ
e2e	58.25% <100.00%> (+0.09%)	⬆️
unit	70.69% <ø> (-0.01%)	⬇️

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