Unable to use tasks apart from AWSCLI behind a proxy

Getting connectivity issues when the all tasks (apart from CLI) are connecting to AWS behind a proxy.

See error for Create/Update Stack: Pipeline
2018-10-31T12:03:07.1190509Z Stack creation request failed with error: 'connect ETIMEDOUT 54.239.39.185:443' { Error: connect ETIMEDOUT 54.239.39.185:443
2018-10-31T12:03:07.1190509Z at Object.exports._errnoException (util.js:1018:11)
2018-10-31T12:03:07.1190509Z at exports._exceptionWithHostPort (util.js:1041:20)
2018-10-31T12:03:07.1190509Z at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1086:14)
2018-10-31T12:03:07.1190509Z message: 'connect ETIMEDOUT 54.239.39.185:443',
2018-10-31T12:03:07.1190509Z code: 'NetworkingError',
2018-10-31T12:03:07.1190509Z errno: 'ETIMEDOUT',
2018-10-31T12:03:07.1190509Z syscall: 'connect',
2018-10-31T12:03:07.1190509Z address: '54.239.39.185',
2018-10-31T12:03:07.1190509Z port: 443,
2018-10-31T12:03:07.1190509Z region: 'eu-west-1',
2018-10-31T12:03:07.1190509Z hostname: 'cloudformation.eu-west-1.amazonaws.com',
2018-10-31T12:03:07.1190509Z retryable: true,
2018-10-31T12:03:07.1190509Z time: 2018-10-31T12:03:07.073Z }

The AWS Cli task works fine and looking at the code I'm guessing it is due to this line of code:

await this.taskParameters.configureHttpProxyFromAgentProxyConfiguration('AWSCLI');

at https://github.com/aws/aws-vsts-tools/blob/develop/Tasks/AWSCLI/helpers/AWSCliTaskOperations.ts#L32

Could this be incorporated into the other tasks

Start in Tasks/AWSCLI/helpers/AWSCliTaskOperations.ts at configureHttpProxyFromAgentProxyConfiguration('AWSCLI'), then compare how the other task implementations configure AWS connections. Reproduce the proxy failure for a non-CLI task and verify that the affected tasks can connect through the proxy without the ETIMEDOUT error.

Written by the indexing model from the issue text.