feat: move deps to playbook

Remove galaxy dependencies from role meta and add explicit
include_role tasks in the playbook instead.

meta/main.yaml

@@ -5,8 +5,4 @@ galaxy_info:
   description: "install and configure an pangolin server"
   license: "MIT"
   role_name: "pangolin"
-dependencies:
+dependencies: []
-  - name: "docker"
-    src: "https://gitlab.simoncor.net/ansible/ans-docker.git"
-    scm: "git"
-    version: "main"