Remove method children from concat

.changeset/floppy-llamas-teach.md

@@ -0,0 +1,10 @@
+---
+"@neo4j/cypher-builder": major
+---
+
+Remove method `.children` from concat clauses:
+
+```js
+const query = Cypher.utils.concat(clause1, clause2);
+query.children; // No longer supported
+```

src/clauses/utils/concat.ts

@@ -52,11 +52,6 @@ export class CompositeClause extends Clause {
         return this._children.length === 0;
     }
 
-    /** @deprecated Children from a composite clause should not be accessed as this will lead to unexpected behaviour */
-    public get children(): Array<CypherASTNode> {
-        return this._children;
-    }
-
     /** @internal */
     public getCypher(env: CypherEnvironment, importWithCypher?: string): string {
         // NOTE: importWithCypher used to pass down import WITH to UNION clauses