docs: Update classDiagram.md

[SahilNagpure07]

📑 Summary

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Fixed typo.

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• 💻 have added necessary unit/e2e tests.
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[codecov]

Codecov Report

Merging #4973 (36a727d) into develop (5f117fc) will decrease coverage by 0.45%.
The diff coverage is n/a.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #4973      +/-   ##
===========================================
- Coverage    80.17%   79.72%   -0.45%     
===========================================
  Files          164      164              
  Lines        13820    13820              
  Branches       693      693              
===========================================
- Hits         11080    11018      -62     
- Misses        2591     2653      +62     
  Partials       149      149              

Flag	Coverage Δ
e2e	85.67% <ø> (-0.56%)	⬇️
unit	42.94% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

see 7 files with indirect coverage changes

[SahilNagpure07]

@sidharthv96 please review

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