Allow to use --proxy on cron job

[shogondo]

I faced a problem that I cannot use --proxy option on cron job with 'Too many arguments.' error.

Currently, /etc/cron.d/codedeploy-agent-update is defined as follows:

# Cron that starts once every day or on reboot, which updates codedeploy-agent.
# This cron file has been fuzzed to run after 10:31:44 every hour.
31 10 * * * root /bin/sleep 44; /opt/codedeploy-agent/bin/update --sanity-check --upgrade rpm
1 * * * * root /bin/sleep 44; /opt/codedeploy-agent/bin/update --sanity-check --downgrade rpm
@reboot root /bin/sleep 45; /opt/codedeploy-agent/bin/update --sanity-check rpm

According to https://github.com/aws/aws-codedeploy-agent/blob/master/bin/update#L135, the update script can be passed up to 4 arguments. So I cannot set proxy like 31 10 * * * root /bin/sleep 44; /opt/codedeploy-agent/bin/update --sanity-check --upgrade --proxy http://x.x.x.x:yyy rpm

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[coveralls]

Coverage remained the same at 91.679% when pulling 1979567 on shoutakenaka:update_with_proxy into 7a58ba9 on aws:master.

[mwjones-aws]

bin/update no longer ships with CodeDeploy Agent, starting with the 1.4.0 release. It is no longer supported.

https://docs.aws.amazon.com/codedeploy/latest/userguide/codedeploy-agent.html#codedeploy-agent-version-history