Enable text-line-height, text-letter-spacing paint properties to format options

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## Motivation

I want to be able to adjust the line-height and letter-spacing of the smaller text "Saint Petersberg"

This becomes more important when two font families are used.

## Design Alternatives

- Contend with spacing feeling off
- For line-height, there are less flexible alternatives like
- Using an exaggerated line-height and increase the label max-width
- Adding an additional line break (which limits control over height value)

## Design

```json
[
"format",
["get", "name_ru"],
{},
"\n",
{},
["get", "name_en"],
{
"font-scale": 0.75,
"text-line-height": 0.2,
"text-letter-spacing": 0.1
}
]
```

Start by tracing the format expression shown in the issue and how text-line-height and text-letter-spacing are handled as paint properties. Verify that both options are accepted and affect the rendered multiline label, including the example values; done means the formatting works when the two font families are used.

Written by the indexing model from the issue text.