Converge on a single build system/specification

[banesullivan]

We seem to have some duplicate build specs between Hatch and the standard project spec

For example, we have two definitions of development dependencies:

with the standard build tools

pyosMeta/pyproject.toml

Lines 39 to 47 in bcb76bd

	[project.optional-dependencies]
	dev = [
	"black",
	"flake8",
	"pre-commit",
	"pytest",
	"pytest-cov",
	"pytest-mock",
	]

and with hatch

pyosMeta/pyproject.toml

Lines 74 to 75 in bcb76bd

	[tool.hatch.envs.test]
	dependencies = ["pytest", "pytest-cov", "coverage[toml]", "pytest-mock"]

This means that if we add a new test dependency it has to be added in two places (which took me a bit to figure out in #301). Perhaps we're doing this wrong and that hatch section should point to the already defined dev dependencies?

I'm not familiar with Hatch or what it provides but it feels a bit redundant here. I'm not against going with Hatch here, I just think we ought to converge on a single spec to prevent needing to update dependencies or scripts in multiple places... perhaps someone more familiar with Hatch can help me correct this?