Modernize PyPI deployment

[jay-m-dev]

Modernize PyPI deployment to use pyproject.toml instead of the legacy setup.py build process.

[jay-m-dev]

It would be a great idea to add a test for the built pip package before pushing it to PyPI.
Description of issue:

• A build configuration can be created such that the folder structure in the pip package could be non-standard and cause import errors.

example pyproject.toml configuration to look into:
[tools.setuptools]
package-dir = {"" = "src"}
packages = [""] // may also need to test if this issue arises specifically due to a mismatch in the package name and folder name (e.g. heros/ vs skheros)

[tool.setuptools.packages.find]
where = ["src"]
#include = ["heros*"] // test if it matters that this is the folder name and not the package name (e.g. skheros instead?)
#exclude = ["tests*"]

The main thing is to ensure package imports work before pushing to PyPI