Update jobs based on testing runtime for 2025.1

Based on [0] only py39 and py312 jobs are in the testing
runtime for 2025.1, updated relevant files accordingly.

[0] https://review.opendev.org/c/openstack/governance/+/926150

Depends-on: https://review.opendev.org/c/openstack/openstack-zuul-jobs/+/926153
Depends-On: https://review.opendev.org/c/openstack/openstack-zuul-jobs/+/929823
Change-Id: I852290979737158e299bda52441d165784ec90dd

.zuul.yaml

@@ -41,11 +41,10 @@
         - neutron-tempest-plugin-dynamic-routing
     experimental:
       jobs:
-        - openstack-tox-py310-with-oslo-master
+        - openstack-tox-py312-with-oslo-master
     periodic-weekly:
       jobs:
         - openstack-tox-py312
-        - openstack-tox-py311
+        - openstack-tox-py312-with-oslo-master
-        - openstack-tox-py310-with-oslo-master
         - neutron-tempest-plugin-dynamic-routing
         - neutron-dynamic-routing-functional

setup.cfg

@@ -6,7 +6,7 @@ description_file =
 author = OpenStack
 author_email = openstack-discuss@lists.openstack.org
 home_page = https://docs.openstack.org/neutron-dynamic-routing/latest/
-python_requires = >=3.8
+python_requires = >=3.9
 classifier =
     Environment :: OpenStack
     Intended Audience :: Information Technology
@@ -17,10 +17,10 @@ classifier =
     Programming Language :: Python :: Implementation :: CPython
     Programming Language :: Python :: 3 :: Only
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.8
     Programming Language :: Python :: 3.9
     Programming Language :: Python :: 3.10
     Programming Language :: Python :: 3.11
+    Programming Language :: Python :: 3.12
 
 [files]
 packages =