chore: Python 3.12 is the floor (NAPALM/driver-standard#6)

netOrk runs every driver in its own containers on Python 3.12, so 3.10
and 3.11 are no longer supported or tested. requires-python, mypy and
ruff move to 3.12, along with what ruff's pyupgrade rules then rewrite.

README.md

@@ -14,7 +14,7 @@ NAPALM community driver for **OPNsense** firewalls (read-only, via REST API).
 
 | Dependency | Minimum version |
 |---|---|
-| Python | 3.10 |
+| Python | 3.12 |
 | NAPALM | 4.0 |
 | napalm-device-types | 4.21.1 |
 | requests | 2.28 |
@@ -212,7 +212,7 @@ python -m venv .venv && .venv/bin/pip install -e ".[dev]"
 ## CI
 
 [.gitea/workflows/ci.yml](.gitea/workflows/ci.yml) calls the shared workflow of the
-driver standard: ruff, mypy, the tests on Python 3.10–3.13 and at the lowest declared
+driver standard: ruff, mypy, the tests on Python 3.12 and 3.13 and at the lowest declared
 versions, bandit, pip-audit and a build check. A release tag publishes to PyPI.
 
 ## License