Request: Generate GroupBy Object Array items in order as listed

REQUEST: I would like Object Array items generated the order they are listed.

I use Pull Requests to create releases and changelogs.

I understand that currently;
- groupBy Objects are generated in the order they are listed.
- groupBy Object Arrays are generated alphabetically.

Below is my configuration. For groupBy "Database" Object, I'd like "vehicle" items then "maintain" items generated in the order as listed.
Instead I always get "maintain" first because of alphabet.

```
module.exports = {
"dataSource": "prs",
"ignoreIssuesWith": [
"wontfix",
"duplicate"
],
"prefix": "",
"onlyMilestones": false,
"groupBy": {
"Housekeeping": ["internal"],
"Database": ["vehicle", "maintain"],
"Enhancements": ["enhancement"],
"Bug Fixes": ["bug"],
"null": ["null"]
},
"template": {
commit: ({ message, url, author, name }) => `- [${message}](${url}) - ${author ? `@${author}` : name}`,
issue: "- {{labels}} {{name}} [{{text}}]({{url}})",
label: "[**{{label}}**]",
noLabel: "closed",
group: "\n#### {{heading}}\n",
changelogTitle: "# Changelog\n\n",
release: "## {{release}} ({{date}})\n{{body}}",
releaseSeparator: "\n---\n\n"
},
"changelogFilename": "CHANGELOG.md"
}
```

首先定位處理 groupBy 設定並排序物件陣列群組的程式碼，使用 issue 中的範例設定作為重現案例。驗證 Database 項目是否依序輸出為 "vehicle" 然後 "maintain"，而不是按字母順序輸出，並確認其他 groupBy 形式的現有排序行為維持不變。

由索引模型根據 Issue 內容生成。