Custom line height not applied when opening files in diff editor

* Configure:
```
"editor.tokenColorCustomizations": {
  "textMateRules": [
    {
      "scope": "entity.name.type.class",
      "settings": {
        "fontSize": 3,
        "lineHeight": 3
      }
    }
  ]
}
```
* Open fresh files with classes in the diff editor after making a change
* :bug: Observe the line height is not getting applied 