APM doesn't respect proxy setting

Prerequisites

[X] Put an X between the brackets on this line if you have done all of the following:
- Reproduced the problem in Safe Mode: https://flight-manual.atom.io/hacking-atom/sections/debugging/#using-safe-mode
- Followed all applicable steps in the debugging guide: https://flight-manual.atom.io/hacking-atom/sections/debugging/
- Checked the FAQs on the message board for common solutions: https://discuss.atom.io/c/faq
- Checked that your issue isn't already filed: https://github.com/issues?utf8=✓&q=is%3Aissue+user%3Aatom
- Checked that there is not already an Atom package that provides the described functionality: https://atom.io/packages

Description

Run the following:

apm config set https-proxy http://localhost:8124
export https_proxy http://localhost:8124
apm install <some-package>

The the following subprocess is created: /usr/share/atom/resources/app/apm/bin/node /usr/share/atom/resources/app/apm/node_modules/npm/node_modules/update-notifier/check.js {"pkg":{"name":"npm","version":"6.2.0"}}

This process tries to connect directly to the requested site on port 443, without going through the proxy.

Steps to Reproduce

See above.

Expected behavior: No connection should be made directly. Ever.

Actual behavior: strace show direct connections to 104.16.18.35:443

Reproduces how often:

100% sure.

Versions

> atom --version
Atom    : 1.38.2
Electron: 2.0.18
Chrome  : 61.0.3163.100
Node    : 8.9.3
> apm --version
apm  2.1.7
npm  6.2.0
node 8.9.3 x64
atom 1.38.2
python 2.7.16
git 2.20.1

Additional Information

None

atom / apm