update min. supported python version

Author: dugalh

.github/workflows/install-test-conda-forge.yml

@@ -12,7 +12,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ macos-latest, ubuntu-latest, windows-latest ]
-        python-version: ['3.8', '3.10', '3.11', '3.12']
+        python-version: ['3.9', '3.13']
 
     steps:
       - name: Check out repository

.github/workflows/install-test-pypi.yml

@@ -9,7 +9,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ macos-latest, ubuntu-latest, windows-latest ]
-        python-version: ['3.8', '3.10', '3.11', '3.12']
+        python-version: ['3.9', '3.13']
 
     steps:
       - name: Check out repository

.github/workflows/install-test-testpypi.yml

@@ -9,7 +9,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ macos-latest, ubuntu-latest, windows-latest ]
-        python-version: ['3.8', '3.10', '3.11', '3.12']
+        python-version: ['3.9', '3.13']
 
     steps:
       - name: Check out repository

.github/workflows/run-integration-tests.yml

@@ -14,7 +14,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ['3.8', '3.10', '3.11', '3.12']
+        python-version: ['3.9', '3.13']
 
     steps:
     - name: Check out repository

.github/workflows/run-unit-tests.yml

@@ -17,8 +17,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ['3.8', '3.10', '3.11', '3.12']
         os: [ macos-latest, ubuntu-latest, windows-latest ]
+        python-version: ['3.9', '3.13']
 
     steps:
     - name: Check out repository

pyproject.toml

@@ -2,7 +2,7 @@
 name = 'homonim'
 description = 'Correct aerial and satellite imagery to surface reflectance.'
 readme = 'README.rst'
-requires-python = '>=3.8'
+requires-python = '>=3.9'
 dependencies = [
     'rasterio>=1.1',
     'opencv-python-headless>=4.5',