Problem Description: With the new RBAC system we can assign Task permissions. Currently user can access `/ui/tasks` page without permissions and can stop pending task without permissions.

Proposed Solution:  

• When user visits Task management page without required permission (`View all tasks`) => display `You do not have permission to perform this action.` page state. (Perhaps hide Task Management item in Menu as well?)
• Hide pending/running/waiting `Stop task` button for users without permission