chore(deps): stop to claim that we support old stuff

It may still work, but the reality is probably that nobody knows.

- Python 3.9.2 is the default version of Python in current Debian oldstable.
  The current Debian stable (12, Bookworm) has already 1 year (june 2023).
- CubicWeb 4.5.2 was published at the end of 2023.

We would have liked to upgrade more.
However the new minimum versions are the ones of an active project.

.gitlab-ci.yml

 ---
 default:
-  image: python:3.7
+  image: python:3.9
 
 include:
   - project: "open-source/gitlab-ci-templates"

cubicweb_s3storage/__pkginfo__.py

@@ -15,7 +15,7 @@
 web = f"https://forge.extranet.logilab.fr/cubicweb/cubes/{distname}"
 
 __depends__ = {
-    "cubicweb": ">= 4.0.0, < 5.0.0",
+    "cubicweb": ">= 4.5.2, < 5.0.0",
     "boto3": None,
 }
 __recommends__ = {}
@@ -24,5 +24,6 @@
     "Environment :: Web Environment",
     "Framework :: CubicWeb",
     "Programming Language :: Python",
+    "Programming Language :: Python :: 3",
     "Programming Language :: JavaScript",
 ]

setup.py

@@ -69,6 +69,7 @@
     author_email=author_email,
     url=web,
     classifiers=classifiers,
+    python_requires=">=3.9.2",
     packages=find_packages(exclude=["test"]),
     install_requires=install_requires,
     include_package_data=True,