fix: Comparison cast for paypal payment verification

[anhanh11001]

Fixes #6411

[iamareebjamal]

Why did you say it worked when it didn't?

[codecov]

Codecov Report

Merging #6412 into development will decrease coverage by 0.02%.
The diff coverage is 0%.

@@              Coverage Diff               @@
##           development   #6412      +/-   ##
==============================================
- Coverage        64.92%   64.9%   -0.03%     
==============================================
  Files              288     288              
  Lines            14912   14912              
==============================================
- Hits              9681    9678       -3     
- Misses            5231    5234       +3

Impacted Files	Coverage Δ
app/api/helpers/payment.py	25% <0%> (ø)	⬆️
app/api/helpers/scheduled_jobs.py	20.93% <0%> (-2.33%)	⬇️

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[anhanh11001]

About the mistake above, I forgot to put change.

Also, I think I should also tell you this: sorry for not testing properly as I couldn't set up my local database so I just create an object manually and test if it matches my postman request, it wasn't proper testing. I should have asked for proper guideline instead of doing this.