Add unit tests for compute_weighted_sum()

[samarth9008]

We want to add unit tests for compute_weighted_sum()

Function location -

kaizenflow/helpers/hpandas.py

Line 1662 in b3469cc

def compute_weighted_sum(

Guides for the test:

• Create multiple small and simple dfs that will be easy to observe and compare (e.g. 2x2 squares with single value in every cell etc.)
• Make a separate test for each index_mode
• Compare outcomes with string signature approach iow you get the output, convert it to string and then check it right inside the test. For ref see tests in amp/helpers/test/test_hpandas.py e.g. Test_merge_dfs1

See unit test doc to follow the code style
Also highly recommend to read this doc before submitting 1st PR

FYI @gpsaggese @sonaalKant @DanilYachmenev

[samarth9008]

@DanilYachmenev If possible can you refine the specs even more? Thank you!

[surbhi498]

I have added the Unit Test Cases for function compute_weighted_sum in test_hpandas.py
The PR link enclosed:
#1041 (comment)

[dremdem]

@surbhi498 Can you add an epic please.
FYI @samarth9008