Do not retrieve magnum's git clone

tasks/pre-install.yml

@@ -77,16 +77,3 @@
     - magnum-directories
     - magnum-logs
     - magnum-system-settings
-
-- name: Retrieve the Magnum Source
-  git:
-    repo: "{{ magnum_git_url }}"
-    version: "{{ magnum_git_install_branch }}"
-    dest: "{{ magnum_git_destination }}"
-    force: "yes"
-  register: magnum_git_clone
-  until: magnum_git_clone |success
-  retries: 5
-  delay: 2
-  tags:
-    - magnum-git-clone