### Bug description

When I use format `gfm` or `commonmrk` and use `quarto render README.qmd` I see the `.md` file popup but then go away. 

When I call `quarto::quarto_render("README.qmd", output_format = "all")` I see the following steps:
* `README.rmarkdown` added
* `README.rmarkdown` deleted
* `README.md` added
* `README.rmarkdown` added
* `README.rmarkdown` deleted
* `README.md` deleted -- 👀 not expecting this step

If I use `docx` instead of `gfm` both formats come back as expected

```r
---
title: "quarto"
format: 
  # commonmark: default
  gfm: default
  revealjs: default
---

## Quarto
```

Using
```
RStudio 2022.07.1 Build 554
Windows 10 Build 19042
```

### `quarto check` Output

```bash
quarto check

[>] Checking Quarto installation......OK
      Version: 99.9.9
      Path: C:\Users\rileyj3\github\quarto-cli\package\dist\bin\
      CodePage: 1252

[>] Checking basic markdown render....OK

[>] Checking Python 3 installation....OK
      Version: 3.9.12
      Path: C:/Users/rileyj3/AppData/Local/Programs/Python/Python39/python.exe
      Jupyter: 4.11.1
      Kernels: python3

[>] Checking Jupyter engine render....OK

[>] Checking R installation...........OK
      Version: 4.2.0
      Path: C:/Users/rileyj3/R/R-4.2.0
      LibPaths:
        - C://Users/rileyj3/R/win-library/4.2/library
      rmarkdown: 2.14
[>] Checking Knitr engine render......OK
```

### `quarto tools check` Output

```bash
[>] Inspecting tools

Tool         Status            Installed     Latest
chromium     Not installed     ---           869685
tinytex      Not installed     ---           v2022.08
```

### Checklist

- [X] [formatted your issue](https://yihui.org/issue/#please-format-your-issue-correctly) so it is easier for us to read?
- [X] included a minimal, fully reproducible example in a single .qmd file? Please provide the whole file rather than the snippet you believe is causing the issue.
- [X] documented the quarto version you're running, by pasting the output from running `quarto check` in the "Quarto Check Output" text area?
- [X] documented the version of the quarto tools you're running, by providing the output from running `quarto tools check` in the "Quarto Tools Check Output" text area?
- [X] documented the RStudio IDE version you're running (if applicable), by providing the value displayed in the "About RStudio" main menu dialog?
- [X] documented which operating system you're running? If on Linux, please provide the specific distribution as well.
- [X] upgraded to the latest version, including your versions of R, the RStudio IDE, and relevant R packages?
2022-08-16T16:51:23Z
rjake
bug
Future
open
Rendering multiple formats not working with markdown variants
https://github.com/quarto-dev/quarto-cli/issues/1929