feat: adapt Vue 3.x (#755)

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packages/vue-identicon/src/util.ts

@@ -0,0 +1,14 @@
+// Copyright 2017-2023 @polkadot/vue-identicon authors & contributors
+// SPDX-License-Identifier: Apache-2.0
+
+import { version } from 'vue';
+
+export function adaptVNodeAttrs (data: Record<string, any>) {
+  if (version.startsWith('3.')) {
+    return data;
+  } else {
+    return {
+      attrs: data
+    };
+  }
+}