Foundry support for include_paths configuration

[0xCalibur]

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https://book.getfoundry.sh/reference/config/solidity-compiler#include_paths

Allows to support folder outside src/ for example. See implementation example here: https://github.com/0xCalibur/hardhat-vscode/commit/864ff3008c25ad9b62de47bda56ad79bc57a70ca