Migrate Home page animation to CSS transitions and remove react-transition-group

[mstange]

Main branch | Deploy preview

This removes our usage of react-transition-group. We were only using it for the horizontal slide-in animation that occurs on the home page when we have a WebChannel and detect that the profiler button is in the toolbar.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 85.38%. Comparing base (2a7d07e) to head (e17e396).
⚠️ Report is 7 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #5649   +/-   ##
=======================================
  Coverage   85.38%   85.38%           
=======================================
  Files         322      322           
  Lines       32099    32101    +2     
  Branches     8840     8849    +9     
=======================================
+ Hits        27408    27410    +2     
  Misses       4260     4260           
  Partials      431      431           

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[canova]

Thanks!