Put cloneData function for slate block, in order to change the uuids of fragments

packages/volto-slate/news/5518.bugfix

@@ -0,0 +1 @@
+When copying a text block—implemented in Slate—that contains UUIDs attached to elements in the data, the UUIDs get copied into the new block, making them not unique. Now instead of duplicating the UUIDs, a new UUID will be generated and assigned to the copy, preserving uniqueness. @dobr1408

packages/volto-slate/src/blocks/Text/index.js

@@ -4,6 +4,9 @@ import TextBlockView from './TextBlockView';
 import TextBlockEdit from './TextBlockEdit';
 import TextBlockSchema from './TextBlockSchema';
 
+import { nanoid } from '@plone/volto-slate/utils';
+import { v4 as uuid } from 'uuid';
+
 import {
   goDown,
   goUp,
@@ -118,6 +121,27 @@ export default function applyConfig(config) {
       addPermission: [],
       view: [],
     },
+    cloneData: (data) => {
+      return [
+        uuid(),
+        {
+          ...data,
+          value: [
+            ...(data?.value || []).map((c) => {
+              return {
+                ...c,
+                children: (c?.children || []).map((childrenData) => {
+                  return {
+                    ...childrenData,
+                    data: { ...childrenData.data, uid: nanoid(5) },
+                  };
+                }),
+              };
+            }),
+          ],
+        },
+      ];
+    },
     blockHasValue: (data) => {
       // TODO: this should be handled better
       return data && !!data.plaintext?.trim();