HTTPCLIENT-2381 Enable automatic mapping

[arturobernalg]

Enable env-proxy support ([HTTPCLIENT-2381](Enable env-proxy support (HTTPCLIENT-2381) – add EnvironmentProxyConfigurer, wire it into HttpClientBuilder, revert extra fallbacks, and introduce JUnit test (System-Lambda) with dep-management cleanup.)) – add EnvironmentProxyConfigurer, wire it into HttpClientBuilder, revert extra fallbacks, and introduce JUnit test (System-Lambda) with dep-management cleanup.

[ok2c]

@arturobernalg Actually I think the fix is misplaced. This logic should go into SystemDefaultRoutePlanner and our code must not change the system properties at all but populate HttpRoutes instead based on environment