fix: Remove duplicated const

Author: caoccao

hivemq-edge-frontend/src/extensions/datahub/utils/datahub.utils.ts

@@ -3,8 +3,6 @@ import { OperationData } from '@datahub/types.ts'
 
 export const DND_DESIGNER_NODE_TYPE = 'application/reactflow;type=designer-node'
 
-export const DND_DESIGNER_NODE_TYPE = 'application/reactflow;type=designer-node'
-
 export const SCRIPT_FUNCTION_SEPARATOR = ':'
 export const SCRIPT_FUNCTION_PREFIX = 'fn'
 export const SCRIPT_FUNCTION_LATEST = 'latest'