code format clean up Repository::Git model

git-svn-id: http://svn.redmine.org/redmine/trunk@12742 e93f8b46-1217-0410-a6f0-8f06a7374b81
remove unneeded Relation#all from Repository::Git model

git-svn-id: http://svn.redmine.org/redmine/trunk@12743 e93f8b46-1217-0410-a6f0-8f06a7374b81