[defaults]
inventory = $INFRASTRUCTURE_REPO/plugins/inventory
roles_path = $INFRASTRUCTURE_REPO/roles:$INFRASTRUCTURE_REPO/roles
filter_plugins = $INFRASTRUCTURE_REPO/plugins/filter_plugins
retry_files_save_path = ~/.ansible-retry
hash_behavior = merge

[ssh_connection]
# this needs the path defined wihtout the use of ENV variables
ssh_args = -F __INFRA_REPO_PATH__/config/private/ssh_config

[defaults]
inventory = $INFRASTRUCTURE_REPO/plugins/inventory
roles_path = $INFRASTRUCTURE_REPO/../roles:$INFRASTRUCTURE_REPO/roles
filter_plugins = $INFRASTRUCTURE_REPO/plugins/filter_plugins
retry_files_save_path = ~/.ansible-retry
hash_behavior = merge

[ssh_connection]
# this needs the path defined wihtout the use of ENV variables
ssh_args = -F __INFRA_REPO_PATH__/config/private/ssh_config

Store Ansible Galaxy roles outside
config: Store Ansible Galaxy roles outside

Store the roles outside the repo by default. This was changed in f78132b6 but did not include a description of why this change was made. 

The path was then duplicated which leads me to think it was maybe not intentional. If we are going to start vendoring of roles we should call that out explicitly.