Bump minor version requirement of symfony/process to ~3.2
Bump minor version requirement of symfony/process to ~3.2

Because \Symfony\Components\Process\InputStream doesn't exist in previous versions.

Big-Shark/grumphp,veewee/grumphp,veewee/grumphp,janvernieuwe/grumphp,phpro/grumphp,phpro/grumphp,janvernieuwe/grumphp,tombevers/grumphp,tombevers/grumphp,Big-Shark/grumphp