Migrate tbump.toml to pyproject.toml

[kratsg]

Summary

See title. Just migrate over.

Additional Information

No response

Code of Conduct

• [X] I agree to follow the Code of Conduct

[kratsg]

Can do something like

[tool.tbump]
field = [
    { name = "release", default = "" },
]
file = [
    { src = "pyproject.toml", version_template = "version = \"{major}.{minor}.{patch}{release}\"" },
]