Fix transport bug

[witjs]

fix a bug

If the environment variable https_proxy’s protocol is HTTP

Then I make a request with URL that starts with HTTPS

The request will use the wrong transport

Transport should be nothing to do with proxy

axios/lib/adapters/http.js

Line 162 in ffea034

var isHttpsProxy = isHttpsRequest && (proxy ? isHttps.test(proxy.protocol) : true);

proxy.protocol should always be undefined

[chinesedfan]

Thanks for your PR. Please add corresponding tests. And in fact, dist files will updated automatically before each release.

[Niek]

Unfortunately this MR does not fix the issue. This issue (HTTPS requests over HTTP proxies are always failing) has been present since at least 3 years. There are at least 2 packages out there that fix this:
https://www.npmjs.com/package/axios-https-proxy-fix (works)
https://www.npmjs.com/package/axios-proxy-fix (doesn't work for me)

This is the required change in code: Sitronik@36c1f46