Bitbucket and possibly GitHub repository validation doesn't respect http proxyhosts java system properties

When a user sets up a Bitbucket repository in Bamboo, and Bamboo needs to access the web through a proxy and therefore has been setup with system properties -Dhttp.proxyHost and -Dhttp.proxyPort, these properties are not respected when talking to Bitbucket during repo setup, editing and validation.

The same issue likely exists when using the GitHub Bamboo repository.