[Tests] Read default tests root folder

[hewigovens]

Description

Fixes https://github.com/trustwallet/wallet-core/issues/2516, read current executable path and find the tests folder, easier to run single test in CLion

How to test

Unit tests

Types of changes

Bug fix (non-breaking change which fixes an issue)

Checklist

• [x] Create pull request as draft initially, unless its complete.
• [x] Add tests to cover changes as needed.
• [x] Update documentation as needed.
• [x] If there is a related Issue, mention it in the description.