Update pyproject.toml

[fernand0]

Updating the license line in pyproject.toml to reference the LICENSE file.

GitHub actions was complaining about the original line.

Error shown (selected relevant line):

configuration error: `project.license` must be valid exactly by one definition (2 matches found):

[fernand0]

I'm not sure, but putting the name of the license in pyproject.toml can produce inconsistencies, if the file license is changed. This will happen too, of course, if it is simply deleted but tests will catch it (?)

[mse11]

@simonw Issue is that repository created from generator template is not using .github/worflow/ files from click-app

Mismatch is in:

• pyproject.tom file is used from click-app repository ( Python >=10 + specific license formatting)
• .github/worflow/publish.yml + test.yml are used from click-app-template-repository (Python "3.8", "3.9" ...)

Visually: