allow for `TESTARGS` in invoke test

[kjaymiller]

Version: 6.0.0b1

Platform: MacOS Arm M2

Description: Description of your issue, stack traces from errors and code that reproduces the issue

Currently the invoke test command pre-configures some commands but pushes you down a few paths:

1. Test all the tests in standalone
2. Test all the tests in a cluster
3. Test all the tests in both

I propose that we add the following to all the tests functions in task.py either:

1. add a TESTARGS parameters that allows for the user to apply their own args to the test
2. add individual parameters for things like test_path, -v (verbosity), -k (keyword)

[mkmkme]

I started looking at this and noticed the following:

invoke functions do support **kwargs but this optional argument doesn't act the way you'd expect it to. The reason for this is that you are able to pass multiple tasks for invoke:

❯ invoke  -h tests
Usage: inv[oke] [--core-opts] tests [--options] [other tasks here ...]

Adding **kwargs to your test actually adds just another argument called --kwargs=STRING:

❯ invoke  -h tests
Usage: inv[oke] [--core-opts] tests [--options] [other tasks here ...]

Docstring:
  Run the valkey-py test suite against the current python,
  with and without libvalkey.

Options:
  -c, --color
  -k STRING, --kwargs=STRING
  -p INT, --protocol=INT
  -u, --uvloop

Oddly enough, **kwargs don't behave the very expected way. If you put --kwargs="a b --foo --bar", you'll get:

kwargs={"kwargs": "a b --foo --bar"}

So for some reason it will be wrapped with a dict!
It gets funnier when you decide to add *args into it!

❯ invoke  tests  s --kwargs="-v -k"
Starting Valkey tests
kwargs: {'args': 's', 'kwargs': '-v -k'}
args: ()

So, even though you added *args, those args were appended to kwargs and args are empty!

---

My proposal in this scenario would be to add --pytest-args argument that would be forwarded directly to pytest. And the user will be able to just invoke tests --pytest-args="-v tests/test_commands.py"

One downside of this approach is that it can clash with --color option we already have. But I'd leave it to user's discretion.

Cc @kjaymiller @aiven-sal @ahmedsobeh. WDYT?

[kjaymiller]

@mkmkme I think that could work, would that change also be available in standalone_tests and cluster_tests?

Most of the testing that I want to do is for smaller tests while implementing.

[mkmkme]

@kjaymiller yes it will.

I'll create a PR with --pytest-args shortly.