Add `forge test` to the foundry CI

[damiramirez]

A new workflow was added to check forge fmt and forge build.

The idea is to add a new check for forge test. Since the code in SetupPaymentsLib.t.sol is commented out, we get an error when we try to run forge test:

No tests found in project! Forge looks for functions that starts with `test`.
Error: No tests to run

There are some comments explaining why the code is commented out.