Composer: Requirements could not be resolved to an installable set of packages

[adriansuter]

I tried to install the Slim-Console today. But composer could not resolve an installable set of packages.

- phpstan/phpstan 0.11.19 requires symfony/console ~3.2 || ~4.0 -> satisfiable by symfony/console[3.2.x-dev, 3.3.x-dev, 3.4.x-dev, 4.0.x-dev, 4.1.x-dev, 4.2.x-dev, 4.3.x-dev, 4.4.x-dev, v3.2.0, v3.2.0-BETA1, v3.2.0-RC1, v3.2.0-R
C2, v3.2.1, v3.2.10, v3.2.11, v3.2.12, v3.2.13, v3.2.14, v3.2.2, v3.2.3, v3.2.4, v3.2.5, v3.2.6, v3.2.7, v3.2.8, v3.2.9, v3.3.0, v3.3.0-BETA1, v3.3.0-RC1, v3.3.1, v3.3.10, v3.3.11, v3.3.12, v3.3.13, v3.3.14, v3.3.15, v3.3.16, v3.3.1
7, v3.3.18, v3.3.2, v3.3.3, v3.3.4, v3.3.5, v3.3.6, v3.3.7, v3.3.8, v3.3.9, v3.4.0, v3.4.0-BETA1, v3.4.0-BETA2, v3.4.0-BETA3, v3.4.0-BETA4, v3.4.0-RC1, v3.4.0-RC2, v3.4.1, v3.4.10, v3.4.11, v3.4.12, v3.4.13, v3.4.14, v3.4.15, v3.4.1
6, v3.4.17, v3.4.18, v3.4.19, v3.4.2, v3.4.20, v3.4.21, v3.4.22, v3.4.23, v3.4.24, v3.4.25, v3.4.26, v3.4.27, v3.4.28, v3.4.29, v3.4.3, v3.4.30, v3.4.31, v3.4.32, v3.4.33, v3.4.34, v3.4.35, v3.4.36, v3.4.37, v3.4.38, v3.4.39, v3.4.4
, v3.4.5, v3.4.6, v3.4.7, v3.4.8, v3.4.9, v4.0.0, v4.0.0-BETA1, v4.0.0-BETA2, v4.0.0-BETA3, v4.0.0-BETA4, v4.0.0-RC1, v4.0.0-RC2, v4.0.1, v4.0.10, v4.0.11, v4.0.12, v4.0.13, v4.0.14, v4.0.15, v4.0.2, v4.0.3, v4.0.4, v4.0.5, v4.0.6,
v4.0.7, v4.0.8, v4.0.9, v4.1.0, v4.1.0-BETA1, v4.1.0-BETA2, v4.1.0-BETA3, v4.1.1, v4.1.10, v4.1.11, v4.1.12, v4.1.2, v4.1.3, v4.1.4, v4.1.5, v4.1.6, v4.1.7, v4.1.8, v4.1.9, v4.2.0, v4.2.0-BETA1, v4.2.0-BETA2, v4.2.0-RC1, v4.2.1, v4.
2.10, v4.2.11, v4.2.12, v4.2.2, v4.2.3, v4.2.4, v4.2.5, v4.2.6, v4.2.7, v4.2.8, v4.2.9, v4.3.0, v4.3.0-BETA1, v4.3.0-BETA2, v4.3.0-RC1, v4.3.1, v4.3.10, v4.3.11, v4.3.2, v4.3.3, v4.3.4, v4.3.5, v4.3.6, v4.3.7, v4.3.8, v4.3.9, v4.4.0
, v4.4.0-BETA1, v4.4.0-BETA2, v4.4.0-RC1, v4.4.1, v4.4.2, v4.4.3, v4.4.4, v4.4.5, v4.4.6, v4.4.7] but these conflict with your requirements or minimum-stability.

Do we need to upgrade phpstan to ^0.12.19?