Add grouping functionality to `Sum`

[mudit2812]

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• [ ] All new features must include a unit test. If you've fixed a bug or added code that should be tested, add a test to the test directory!

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• [ ] Ensure that the test suite passes, by running make test.

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Context:

Description of the Change:

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[mudit2812]

[sc-55328]

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 99.63%. Comparing base (3bb04be) to head (d65782e). Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5179      +/-   ##
==========================================
- Coverage   99.63%   99.63%   -0.01%     
==========================================
  Files         400      400              
  Lines       37132    36870     -262     
==========================================
- Hits        36998    36735     -263     
- Misses        134      135       +1     

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