[dev] pass process.exit() to child processes

[waynevanson]

- Do you want to request a feature or report a bug?
Bug

- What is the current behavior?
Pressing CTRL + C after running netlify dev:exec "parcel src/index.html" netlify dev -c parcel src/index.html closes only the netlify server. It should close both, so when I restart the server it can run both again. Instead, I end up with x11 servers running.

edit: I'm using the TOML to set the command, so I changed above to match.

- If the current behavior is a bug, please provide the steps to reproduce.
These are mentioned above.

- What is the expected behavior?
Both servers close when I press CTRL + C on keyboard in terminal

- Local Environment Information

────────────────────┐
 Environment Info   │
────────────────────┘

  System:
    OS: Linux 5.3 Ubuntu 19.10 (Eoan Ermine)
    CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
  Binaries:
    Node: 13.1.0 - ~/.nvm/versions/node/v13.1.0/bin/node
    Yarn: 1.19.2 - /usr/bin/yarn
    npm: 6.13.0 - ~/.nvm/versions/node/v13.1.0/bin/npm
  Browsers:
    Chrome: 78.0.3904.108

I'd love to write a pull on this.

[RaeesBhatti]

@waynevanson Thanks for reporting this. A PR would be very welcome!

[cco3]

This still seems to be a problem when using "--offline --dir"

[cco3]

I just tried 2.35.0 and still have a problem when using --dir. No --dir flag works fine now.

@RaeesBhatti Can you confirm that the fix should work with --dir?

[RaeesBhatti]

Thank you for your patience. This is no longer a problem. Please upgrade to latest version netlify-cli@2.45.0 and let us know if the issue persists.