[BUG] Maxprice endpoint returning invalid values
**Describe the bug**
`/products/maxprice` endpoint seems to return incorrect value. On our demo it returns 100, while price of the biggest product is 5.

**To Reproduce**
Steps to reproduce the behavior:
Open https://api.bitcartcc.com/products/maxprice returns 100, while https://api.bitcartcc.com/products?store=1 returns products where maximum price is 5.

**Expected behavior**
maxprice returns 5

**Screenshots**
If applicable, add screenshots to help explain your problem.
![изображение](https://user-images.githubusercontent.com/39452697/92948787-9a3eca00-f462-11ea-8e80-58863d4c71eb.png)


**Desktop (please complete the following information):**
 - OS: Linux
 - Version master branch
