Upgrade symfony/expression-language

[moniprecup]

Hi,
Do you think it's safe to upgrade the bundle to use symfony/expression-language ^4.0? Currently it's set to ~2.3|~3.0
We are using Symfony Flex (which needs ^4.0) and downgrading is not an option.

Thanks!

[yanc3k]

Not sure. Have you tried if it would work? If so, I'd really appreciate a PR. ;)