Fix: dangling internal links after removing sockets

This is a follow up for rBd5e73fa13dd275fb9c76b1e41142ab086dd2e6be.
The issue was found with the file in T95997.

source/blender/blenkernel/intern/node.cc

@@ -1973,6 +1973,8 @@ void nodeRemoveAllSockets(bNodeTree *ntree, bNode *node)
     }
   }
 
+  BLI_freelistN(&node->internal_links);
+
   LISTBASE_FOREACH_MUTABLE (bNodeSocket *, sock, &node->inputs) {
     node_socket_free(sock, true);
     MEM_freeN(sock);