[BUG] Error occurs when executing updateLIFFApp in LiffClient

[odanado]

Bug Report

Describe the bug
I found that an error occurs when I execute updateLIFFApp in LiffClient.

To Reproduce

Steps to reproduce the behavior:

1. Run this code

import * as line from "@line/bot-sdk";

const liffClient = new line.liff.LiffClient({
  channelAccessToken: process.env.LINE_TOKEN,
});

const res = await liffClient.updateLIFFApp("2006142821-LN7nErlM", {
  view: {
    url: "https://new2.example.com",
  },
});
consola.log("res", res);

2. Get an error

$ node run.js
undefined:1


SyntaxError: Unexpected end of JSON input
    at JSON.parse (<anonymous>)
    at parseJSONFromBytes (node:internal/deps/undici/undici:5472:19)
    at successSteps (node:internal/deps/undici/undici:5454:27)
    at fullyReadBody (node:internal/deps/undici/undici:4381:9)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async consumeBody (node:internal/deps/undici/undici:5463:7)
    at async LiffClient.updateLIFFAppWithHttpInfo (file:///path/to/repo/node_modules/@line/bot-sdk/dist/liff/api/liffClient.js:124:43)
    at async LiffClient.updateLIFFApp (file:///path/to/repo/node_modules/@line/bot-sdk/dist/liff/api/liffClient.js:109:17)
    at async file:///path/to/repo/run.js:7:13

Node.js v22.6.0

Expected behavior

No errors should occur.

Screenshots
If applicable, add screenshots to help explain your problem.

Environment (please complete the following information):

• OS: macOS 14.5
• Node.js Version 22.6.0
• line-bot-sdk-nodejs version(s) 9.4.0

Additional context

An error occurred in the function call, but the URL was updated, so the API execution was successful.

I have also confirmed that the following shell script runs successfully.

set -uex

curl -vvv -X PUT https://api.line.me/liff/v1/apps/2006142821-LN7nErlM \
-H "Authorization: Bearer ${LINE_TOKEN}" \
-H "Content-Type: application/json" \
-d '{
    "view": {
        "url": "https://new.example.com"
    }
}'

It is likely that the error is occurring because the response body from the API is an empty string, which cannot be converted to JSON.
ref:

line-bot-sdk-nodejs/lib/liff/api/liffClient.ts

Line 179 in 365bb03

return { httpResponse: res, body: await res.json() };