Remove support/testing for 3.9

The next release will not support 3.9

Author: rocky

.github/workflows/ubuntu.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ['3.13', '3.9', '3.10', '3.11', '3.12']
+        python-version: ['3.13', '3.10', '3.11', '3.12']
     steps:
     - uses: actions/checkout@v4
     - name: Set up Python ${{ matrix.python-version }}

pyproject.toml

@@ -34,7 +34,6 @@ classifiers = [
     "Intended Audience :: Science/Research",
     "License :: OSI Approved :: GNU General Public License v3 (GPLv3)",
     "Programming Language :: Python",
-    "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",