feat(settings): introduce setting to disable container caps for non-admins (#4109)

* feat(settings): introduce settings to allow/disable

* feat(settings): update the setting

* feat(docker): prevent user from using caps if disabled

* refactor(stacks): revert file

* style(api): remove portainer ns

api/http/handler/stacks/stack_create.go

@@ -173,6 +173,10 @@ func (handler *Handler) isValidStackFile(stackFileContent []byte, settings *port
 		if !settings.AllowDeviceMappingForRegularUsers && service.Devices != nil && len(service.Devices) > 0 {
 			return errors.New("device mapping disabled for non administrator users")
 		}
+
+		if !settings.AllowContainerCapabilitiesForRegularUsers && (len(service.CapAdd) > 0 || len(service.CapDrop) > 0) {
+			return errors.New("container capabilities disabled for non administrator users")
+		}
 	}
 
 	return nil