Remove dockerproject_.+_repo_.+ variables (#5662)

This 38688a4486 change replaces the
value for dockerproject_.+_repo_.+ docker variables but their new
value was previously defined in other variables. This change removes
the dockerproject_.+_repo_.+ docker variables in favor of the older
ones.

roles/container-engine/docker/vars/ubuntu-arm64.yml

@@ -33,7 +33,7 @@ docker_repo_info:
 
 dockerproject_repo_key_info:
   pkg_key: apt_key
-  url: '{{ dockerproject_apt_repo_gpgkey }}'
+  url: '{{ docker_debian_repo_gpgkey }}'
   repo_keys:
     - 58118E89F3A912897C070ADBF76221572C52609D
 
@@ -41,6 +41,6 @@ dockerproject_repo_info:
   pkg_repo: apt_repository
   repos:
     - >
-       deb {{ dockerproject_apt_repo_base_url }}
+       deb {{ docker_debian_repo_base_url }}
        {{ ansible_distribution|lower }}-{{ ansible_distribution_release|lower }}
        main