Improve ReactComponent ready promise handling

[philippjfr]

Follow up to #8602

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 85.78%. Comparing base (b0d6e89) to head (539c425).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #8603       +/-   ##
===========================================
+ Coverage   69.71%   85.78%   +16.06%     
===========================================
  Files         349      350        +1     
  Lines       56932    56933        +1     
===========================================
+ Hits        39692    48839     +9147     
+ Misses      17240     8094     -9146     

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