Fix test for options.cleanup

[ehmicky]

The unit test for options.cleanup has several issues and wasn't checking this feature properly.

It first noticed that some lines of code of this feature were not test covered. Then I saw some inconsistencies between the names of the tests and which signals were triggered:

test('cleanup - SIGINT', spawnAndKill, 'SIGINT', true);
test('cleanup - SIGKILL', spawnAndKill, 'SIGTERM', true);
test('cleanup false - SIGINT', spawnAndKill, 'SIGTERM', false);
test('cleanup false - SIGKILL', spawnAndKill, 'SIGKILL', false);

Digging deeper, the unit test was not checking the feature properly. This fixes it and also removes any timeout, making it more predictable.

[sindresorhus]

Good find 👌