feat: support proxy for outgoing traffic

[juldanherglo]

I have the requirement that our selfhosted gitlab-runners need to use a proxy for outgoing traffic. This solved the problem.

Is that something that you would consider in a PR? Or do you maybe even have a better solutions?

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[sethvargo]

Hi @juldanherglo

We are standardizing on actions/http-client because that's what GitHub recommends for proxy settings on self-hosted runners (https://docs.github.com/en/actions/hosting-your-own-runners/using-a-proxy-server-with-self-hosted-runners). I added support in #218.

[juldanherglo]

Hi @juldanherglo

We are standardizing on actions/http-client because that's what GitHub recommends for proxy settings on self-hosted runners (https://docs.github.com/en/actions/hosting-your-own-runners/using-a-proxy-server-with-self-hosted-runners). I added support in #218.

Thank you, @sethvargo . I tested #218 and it works as well. There was one warning though:

(node:18684) [DEP0005] DeprecationWarning: Buffer() is deprecated due to security and usability issues. Please use the Buffer.alloc(), Buffer.allocUnsafe(), or Buffer.from() methods instead.