content_test.yml is gone, can not set new docker ports

[irichmondge]

if a local splunkd or a local proxy is running on your machine or other things that might be listening to your local ports 8000,8088,8089 etc. ..running contentctl test does not work as it can't bind to those ports. Need a way to pass in alternate ports or a way to configure this. IE: Bring the content_test.tml back.

https://github.com/splunk/contentctl/blob/main/contentctl/objects/config.py#L394