PE-834, PE-424: update tests for changes in Puppet::CloudPack.http_request

This patch updates test of the Puppet::CloudPack.http_request method
which now uses objects of type Puppet::Network::HTTP::Connection
for http requests. Previously it used to use objects of type Net::HTTP.
PE-834, PE-424: remove unused test code pieces
PE-834, PE-424: remove extra whitespace