feat(rest-api-client): Add method for uninstall plugin

[shabaraba]

Why

• Support plugin.uninstallPlugin method to be able to uninstalls a plug-in from the Kintone environment.

What

• Add a document for the new method.
• Add new unit tests.

How to test

1. prepare a zip file for a plug-in.
2. run below code and check logs:

import {KintoneRestAPIClient} from '@kintone/rest-api-client';

const client = new KintoneRestAPIClient();

// Upload a file and attach it to a record
const resp = await client.file.uploadFile({
  file: {
    path: "./files/plugin.zip"
  }
});

const fileKey = resp.fileKey;
console.log(fileKey);

if (typeof fileKey == "string") {
  const pluginId = (await client.plugin.installPlugin({fileKey: fileKey})).id;
  console.log(pluginId);
  console.log(await client.plugin.getPlugins({}));

  await client.plugin.uninstallPlugin({id: pluginId});
  console.log(await client.plugin.getPlugins({}));
}

Checklist

• Read CONTRIBUTING.md
• Updated documentation if it is required.
• Added tests if it is required.
• Passed pnpm lint and pnpm test on the root directory.

[tasshi-me]

LGTM!