Bump github.com/docker/docker from 1.4.2-0.20200214221943-d8772509d1a2 to 27.0.0+incompatible in /tests/integration/functional

Bump github.com/docker/docker from 1.4.2-0.20200214221943-d8772509d1a2 to 27.0.0+incompatible in /tests/integration/functional #24