Steps to reproduce:

1. Install clean installation of Ibexa DXP.
2. Run the php bin/console ibexa:encore:compile with the --timeout argumnet, e.g. php bin/console ibexa:encore:compile --timeout 500.

Result:

Command throws TypeError with message:
Argument 5 passed to Symfony\Component\Process\Process::fromShellCommandline() must be of the type float or null, string given.

Expected result:

The command should complete successfully.