Bad highlighting of nested code chunks in R Markdown documents

[arnaudgallou]

vscode-R incorrectly highlights nested code chunks in R Markdown documents, stopping after the first closing chunk. E.g.:

````{verbatim}

```{r}
foo <- 1
```

````

produces:

I'd expect to have the outermost chunk (verbatim here) fully highlighted. Note that the quarto extension highlights nested code chunks properly. That would be great to get this work for .Rmd files too though.

My system:

• OS: macOS 12.3.1
• VSCode Version: 1.87.1
• R version: 4.3.2
• vscode-R version: 2.8.2