YAML auto-format defaults to double quotes, with no option to choose single quotes

**Is your feature request related to a problem? Please describe.**
When I'm editing an Actions YAML file, the auto-format is triggered every time I save.
The auto-format executed by this GitHub Actions extension switches the single-quoted strings in my Actions YAML to double-quoted.
It's frustrating to have to undo these quoting changes elsewhere, usually when staging/committing changes in version control.

**Describe the solution you'd like**
Other VSCode extensions offer a simple boolean checkbox option for single/double quoting style.

**Additional context**

Start by locating the YAML auto-format implementation and its VS Code settings. Confirm how formatting is triggered on save, then define completion around a user-selectable single- or double-quote style that avoids unrelated quote changes.

由索引模型根據 Issue 內容生成。