Test args are not respected by `service_test`

[engnatha]

Thanks for creating this module! I'm enjoying the language-agnostic way of managing test dependencies. In adopting this for a repository, I discovered that custom args supplied to the underlying test target got dropped when being executed by service_test. Our use of the rules_python py_test has some custom args specified to control how pytest is invoked under the hood.

We are working around this in our macros to pass the same args we use in py_test to the service_test target and it all works fine that way. Curious to get some thoughts on if this is the desired behavior or if there's any interest in preserving the args present in the test target that service_test references.

[dzbarsky]

I would love to make it work but I'm not sure it's possible right now given https://github.com/bazelbuild/bazel/issues/26750 (I'd rather not copy-pasta that polyfill). If you have a better workaround, let me know, or feel free to +1 that Bazel issue!