[FEATURE REQ] - Single Configuration YAML file with option of overriding values at run time

[GaurSumit]

Please describe the feature.

I am not sure if this is already doable in the existing setup, but would like to see if there is a possibility where we could maintain a single publisher configuration file which can be then tokenize to override the value of different environment using Azure DevOps Variable group or using a variable file in Github.

[github-actions]

  Thank you for opening this issue! Please be patient while we will look into it and get back to you as this is an open source project. In the meantime make sure you take a look at the [closed issues](https://github.com/Azure/apiops/issues?q=is%3Aissue+is%3Aclosed) in case your question has already been answered. Don't forget to provide any additional information if needed (e.g. scrubbed logs, detailed feature requests,etc.).
  Whenever it's feasible, please don't hesitate to send a Pull Request (PR) our way. We'd greatly appreciate it, and we'll gladly assess and incorporate your changes.

[anotherRedbeard]

HI @GaurSumit currently the run-publisher-with-env.yaml file expects the configuration in a path (as a file). While I haven't tried this, you should be able to do something like that in either AzDO or Github so long as the output is a file and then feed that into the publisher.