fix: edit segment missing space between buttons (#6826)

Co-authored-by: xc Dou <xcdou@192.168.88.89>

web/app/components/datasets/documents/detail/completed/index.tsx

@@ -142,6 +142,7 @@ const SegmentDetailComponent: FC<ISegmentDetailProps> = ({
             </Button>
             <Button
               variant='primary'
+              className='ml-3'
               onClick={handleSave}
               disabled={loading}
             >