Bestsellers report counts sales incorrectly

[RomanovM]

nopCommerce version: 4.30

I started to debug the code, at some point in the past someone added in the Category to the query for the best seller report and because of that left join it will count your sales 1 time for each category that product is in. in my case i had a few of my best sellers in two categories and there for my sales were doubled for them.
I would assume that sales for an order item should be counted only once, no matter how many categories that product is in.
While I just mention this bug for the best sellers report, it might be a good idea to make sure other reports do not have the same issue.

Steps to reproduce the problem: map a product to multiple categories, makes some sales and view the best sellers report.

Source: https://www.nopcommerce.com/en/boards/topic/85001/best-selling-report-counts-sales-incorrectly

[YetAnotherDev]

I submitted this bug on the forum, please let me know if you have any issues reproducing it or if i can provide more information on this issue.

[holydk]

Closed #4956