No syntax highlight in workflow files

**Describe the bug**
I have the following VS Code configuration:

```json
"[github-actions-workflow]": {
"editor.defaultFormatter": "github.vscode-github-actions",
"editor.formatOnSave": true,
"editor.tabSize": 2,
},
```

Yet, when trying to modify `.github/workflows/test.yml`, I get no syntax highlight for the file, despite being correctly recognized as a `Github Actions Workflow`.


**To Reproduce**
Steps to reproduce the behavior:
1. With this workflow '...'
2. Do this '...'
3. See error

**Expected behavior**
A clear and concise description of what you expected to happen.

**Screenshots**
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**Extension Version**
`v1.x.y`

**Additional context**
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