backstop reference fails to launch browser on windows

On my windows 10 machine the `backstop reference` command fails with the following error:
```
COMMAND | Command "reference" ended with an error after [1.604s]
COMMAND | Error: Failed to launch the browser process!

TROUBLESHOOTING: https://github.com/puppeteer/puppeteer/blob/master/docs/troubleshooting.md

at onClose (C:\Users\npalmer\AppData\Roaming\nvm\v10.16.3\node_modules\backstopjs\node_modules\puppeteer\lib\Launcher.js:750:14)
at ChildProcess.helper.addEventListener (C:\Users\npalmer\AppData\Roaming\nvm\v10.16.3\node_modules\backstopjs\node_modules\puppeteer\lib\Launcher.js:740:61)
at ChildProcess.emit (events.js:203:15)
at Process.ChildProcess._handle.onexit (internal/child_process.js:248:12)
```

This happens even with the default config created by `backstop init`. I tried adding `ignoreDefaultArgs: ['--disable-extensions']` and `args: ['--disable-setuid-sandbox']` to `engineOptions` but that didn't change anything.