pyproject.toml: change license table to text
set license SPDX compliant name
name = "aqtinstall"
description = "Another unofficial Qt installer"
readme = "README.rst"
-license = {file = "LICENSE"}
+license = { text = "MIT License"}
authors = [
{name = "Hiroshi Miura", email = "miurahr@linux.com"},
]
