npm audit fix related to https-proxy-agent

[christianheine]

npm audit lists two high vulnerabilities related to https-proxy-agent during install (of this repo).

npm install
...
found 2 high severity vulnerabilities

npm audit fix updates https-proxy-agent from version 2.2.2 to 2.2.4.

npm audit
                                                                                
                       === npm audit security report ===                        
                                                                                
# Run  npm update https-proxy-agent --depth 3  to resolve 2 vulnerabilities
┌───────────────┬──────────────────────────────────────────────────────────────┐
│ High          │ Machine-In-The-Middle                                        │
├───────────────┼──────────────────────────────────────────────────────────────┤
│ Package       │ https-proxy-agent                                            │
├───────────────┼──────────────────────────────────────────────────────────────┤
│ Dependency of │ codecov [dev]                                                │
├───────────────┼──────────────────────────────────────────────────────────────┤
│ Path          │ codecov > teeny-request > https-proxy-agent                  │
├───────────────┼──────────────────────────────────────────────────────────────┤
│ More info     │ https://npmjs.com/advisories/1184                            │
└───────────────┴──────────────────────────────────────────────────────────────┘


┌───────────────┬──────────────────────────────────────────────────────────────┐
│ High          │ Machine-In-The-Middle                                        │
├───────────────┼──────────────────────────────────────────────────────────────┤
│ Package       │ https-proxy-agent                                            │
├───────────────┼──────────────────────────────────────────────────────────────┤
│ Dependency of │ puppeteer [dev]                                              │
├───────────────┼──────────────────────────────────────────────────────────────┤
│ Path          │ puppeteer > https-proxy-agent                                │
├───────────────┼──────────────────────────────────────────────────────────────┤
│ More info     │ https://npmjs.com/advisories/1184                            │
└───────────────┴──────────────────────────────────────────────────────────────┘

Running npm test results in

  2720 passing (46s)
  24 pending

There seems to be no open issue related to this - and since this was quickly fixed, I decided to rather create directly create a PR. Hope this is ok.