pyproject.toml: Constrain the setuptools version

PEP 639 describing `license` and `license-files` is supported in setuptools
starting from version 77.0.3:
https://packaging.python.org/en/latest/guides/writing-pyproject-toml/#license-and-license-files

Let's add this requirement to `pyproject.toml`.

Author: a13xp0p0v

pyproject.toml

@@ -1,5 +1,5 @@
 [build-system]
-requires = ["setuptools"]
+requires = ["setuptools >= 77.0.3"]
 build-backend = "setuptools.build_meta"
 
 [tool.setuptools.packages.find]