[FIX] Deprecate setup_requires for pyproject.toml

Follow PEP 517/518 packaging standards to avoid dependency issues.

The old definition is kept for Python 2.7, as it seems to be
incompatible.

pyproject.toml

@@ -0,0 +1,10 @@
+[build-system]
+requires = [
+    "setuptools>=61.0.0",
+    "setuptools_scm>=8.0.0; python_version >= '3.7'",
+    "setuptools_scm<6.0.0; python_version < '3.7'",
+    "wheel"
+]
+build-backend = "setuptools.build_meta"
+
+[tool.setuptools_scm]

requirements.txt

@@ -4,4 +4,4 @@ flake8
 pep8-naming
 lxml<=4.3.4
 psycopg2==2.7.3.1
-setuptools<58.0
+setuptools<58.0 ; python_version <= '2.7'

setup.py

@@ -4,8 +4,6 @@
 
 from setuptools import setup
 
-import openupgradelib
-
 with open("README.rst") as readme_file:
     readme = readme_file.read()
 
@@ -24,24 +22,21 @@
 setup(
     name="openupgradelib",
     use_scm_version=True,
-    description=openupgradelib.__doc__,
+    description="""A library with support functions to be called from Odoo \
+migration scripts.""",
     long_description=readme + "\n\n" + history,
-    author=openupgradelib.__author__,
-    author_email=openupgradelib.__email__,
+    author="Odoo Community Association (OCA)",
+    author_email="[email protected]",
     url="https://github.com/OCA/openupgradelib",
     packages=["openupgradelib"],
     include_package_data=True,
-    setup_requires=[
-        "setuptools_scm<6.0.0; python_version <= '3.6'",
-        "setuptools_scm; python_version > '3.6'",
-    ],
     install_requires=[
         "lxml",
         "cssselect",
         'importlib_metadata; python_version<"3.8"',
     ],
     python_requires=">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*",
-    license=openupgradelib.__license__,
+    license="AGPL-3",
     zip_safe=False,
     keywords="openupgradelib",
     classifiers=[