Drop support for Python 3.8 and 3.9

Change-Id: I901fe1618f86236e381e9d19ae815e1befa24e55
Signed-off-by: Ivan Anfimov <lazekteam@gmail.com>

releasenotes/notes/drop-python-38-and-39.yaml

@@ -0,0 +1,4 @@
+---
+upgrade:
+  - |
+    Support for Python 3.8 and 3.9 has been dropped.

setup.cfg

@@ -7,7 +7,7 @@ description_file = README.rst
 description-content-type = text/x-rst
 license = Apache-2.0
 url = https://docs.openstack.org/freezer/latest/
-python_requires = >=3.8
+python_requires = >=3.10
 classifier =
     Development Status :: 5 - Production/Stable
     Environment :: OpenStack
@@ -17,21 +17,15 @@ classifier =
     Intended Audience :: System Administrators
     Operating System :: OS Independent
     Operating System :: POSIX :: Linux
+    Topic :: Internet :: WWW/HTTP
     Programming Language :: Python
     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
-    Topic :: Internet :: WWW/HTTP
-keywords =
-    horizon
-    freezer
-    backup
-    openstack
+    Programming Language :: Python :: 3.13
 
 [files]
 packages =