Please upgrade rimraf version in package.json to fix the exception by fixWinEPERM

[dsheiko]

Currently (Puppeteer 2.1.1) on Windows 10 throws

AssertionError [ERR_ASSERTION]: The expression evaluated to a falsy value:                                      
  assert(er instanceof Error)
  at fixWinEPERM (.\node_modules\rimraf\rimraf.js:175:5)

pretty much the same as described here isaacs/rimraf#155

My guess, it happens when puppeteer removes tmp folder on this.proc exit event:
https://github.com/puppeteer/puppeteer/blob/master/lib/Launcher.js#L99

However, if one updates the rimraf to the latest version, everything works fine.
E.g.

cd node_modules/puppeteer
npm i rimraf@latest

P.S. I'm running puppeteer with the following options:

await puppeteer.launch(
    "product": "firefox",
    "headless": false,
    "devtools": false,
    "ignoreHTTPSErrors": false,
    "args": [
      "--wait-for-browser"
    ],
    "executablePath": "C:\\Program Files (x86)\\Nightly\\firefox.exe"
  });

[aslushnikov]

For the record: this was investigated in isaacs/rimraf#208 and fixed with isaacs/rimraf@aa50e02