Integration tests: split up Docker setup, move docker_compose tests into own group (#718)

* Rename setup role.

* Create new CI group 6, and move docker_compose v1 tests into there.

* Split up Docker setup in integration tests.

* Change setup_docker_compose_v1 to install its own Docker SDK for Python.

* Docker SDK for Python not needed to set up registry or query host info.

tests/integration/targets/setup_docker_python_deps/defaults/main.yml

@@ -0,0 +1,12 @@
+---
+# Copyright (c) Ansible Project
+# GNU General Public License v3.0+ (see LICENSES/GPL-3.0-or-later.txt or https://www.gnu.org/licenses/gpl-3.0.txt)
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+docker_pip_api_packages:
+  - requests
+  # - paramiko
+  # - pyOpenSSL
+
+docker_pip_api_packages_python2:
+  - backports.ssl-match-hostname