Make minimum python version to be 3.10

Author: zhubonan

.github/workflows/ci.yml

@@ -34,7 +34,7 @@ jobs:
 
     strategy:
       matrix:
-        python-version: ['3.9', '3.10', '3.11', '3.12']
+        python-version: ['3.10', '3.11', '3.12']
 
     services:
       rabbitmq:
@@ -70,7 +70,7 @@ jobs:
 
     strategy:
       matrix:
-        python-version: ['3.9']
+        python-version: ['3.10']
 
     steps:
     - uses: actions/checkout@v2

.readthedocs.yml

@@ -3,7 +3,7 @@ version: 2
 build:
   os: ubuntu-22.04
   tools:
-    python: '3.9'
+    python: '3.10'
   apt_packages:
   - gfortran      # This is necessary for the `sisl` dependency of `aiida-siesta`
 

pyproject.toml

@@ -11,7 +11,6 @@ classifiers = [
   'Operating System :: POSIX :: Linux',
   'Operating System :: MacOS :: MacOS X',
   'Programming Language :: Python',
-  'Programming Language :: Python :: 3.9',
   'Programming Language :: Python :: 3.10',
   'Programming Language :: Python :: 3.11',
   'Programming Language :: Python :: 3.12'