I tried to install the sprint extension on a fresh install with latest phabricator and latest sprint extension from git hub. I kept getting errors the error in title of this task and error log helped me trace it to the file located here: sprint/src/application/SprintApplication.php
I found commenting the following lines and clearing op cache fixed it:
60 //ManiphestEditStatusCapability::CAPABILITY => array(), 61 //ManiphestEditAssignCapability::CAPABILITY => array(), 62 //ManiphestEditPoliciesCapability::CAPABILITY => array(), 63 //ManiphestEditPriorityCapability::CAPABILITY => array(), 64 //ManiphestEditProjectsCapability::CAPABILITY => array(), 65 //ManiphestBulkEditCapability::CAPABILITY => array(),