fixup! plugins: make rpc_command hook chainable

lightningd/jsonrpc.c

@@ -812,7 +812,7 @@ rpc_command_hook_callback(struct rpc_command_hook_payload *p,
 		/* We need to make copies here, as buffer and tokens
 		 * can be reused. */
 		p->custom_replace = json_tok_copy(p, tok);
-		p->custom_buffer = tal_strdup(p, buffer);
+		p->custom_buffer = tal_dup_talarr(p, char, buffer);
 		return true;
 	}