GSW-1838 test: sqrt_price_math unitest (#425)

* refactor: sqrt_price_math
- added testcase

* refactor: add test code and comments

- fix test fail issue

* refactor: Overflow check for type conversion to int256 in delta amount calculation

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Co-authored-by: 0xTopaz <[email protected]>
Co-authored-by: 0xTopaz <[email protected]>

Author: 3 people