Fix: Fixed the issue that the knowledge graph could not be displayed #8890 (#8891)

### What problem does this PR solve?

Fix: Fixed the issue that the knowledge graph could not be displayed
#8890

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

web/src/pages/add-knowledge/components/knowledge-graph/util.ts

@@ -86,9 +86,7 @@ export const buildNodesAndCombos = (nodes: any[]) => {
   const nextNodes = nodes.map((x) => {
     return {
       ...x,
-      combo:
-        combos.find((y) => y.data.label === findCombo(x?.communities))?.id ??
-        null,
+      combo: combos.find((y) => y.data.label === findCombo(x?.communities))?.id,
     };
   });