Fixed unexpected auth popup in eclipse

OkHttpClient was misconfigured to always delegate to the jvm default
Authenticator. This did not cause any problems on command line
because default authenticator was null, but resulted in unexpected
username/password authentication dialog in m2e.

See https://bugs.eclipse.org/440273 for original bug report.

Signed-off-by: Igor Fedorenko <igor@ifedorenko.com>