NXCM-5206: NEXUS-5585: Bumped HC4 version to 4.2.5

For NXCM-5206 it contains fix for following issue:
https://issues.apache.org/jira/browse/HTTPCLIENT-1340

For NEXUS-5585: it _might_ fix some NTLM/proxy/407 related issues
fixed in 4.2.3 release of HC4