fix: use proxy only for remote requests

[martinfrancois]

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Since there are no tests for http-client yet, it would be quite a lot of work to add them. Also, the method which was changed useProxySettings is private and therefore more difficult to test.

What is the current behavior?

With a proxy set according to https://docs.nativescript.org/tooling/docs-cli/general/proxy-set when running unit tests with tns test android for example, requests to localhost are being made. Depending on the corporate proxy environment, those requests could be blocked or the proxy can't handle the request, since localhost is not a remote target. This makes running unit tests with NativeScript impossible in corporate proxy environments, causing exceptions interrupting the test execution. Also, it doesn't make sense to make requests to localhost through a proxy, so this will not have any negative effects.

What is the new behavior?

When requests are being made to localhost or 127.0.0.1, even when a proxy is set, the proxy will not be used. Unit tests can be excecuted successfully in an environment with a corporate proxy.

Partially fixes #2313.
A user-defined NO_PROXY is not implemented, but allows for requests to localhost to work properly. Should there be further need to customize which requests should not use the proxy, this could be implemented in a separate PR, but would require discussion on the implementation details.

[Fatme]

test cli-smoke

[Fatme]

@martinfrancois,

Thank you for this PR!

If this is your first contribution to NativeScript, you are eligible for our NativeScript First-Time Contribution program. More info can be found here.

[martinfrancois]

@Fatme,

You're welcome! Thanks for merging it!

It's indeed my first contribution to NativeScript. Thanks for letting me know!