Fix CI docs job failure: use Python 3.10 instead of 3.9

The docs job was configured to use Python 3.9, but pyproject.toml
requires Python >=3.10. This caused `pip install ".[docs]"` to fail
because the package itself cannot be installed on Python 3.9.

Also updates:
- actions/checkout and actions/setup-python to v4/v5 in test and
  deploy jobs (docs job already used v4/v5)
- Python classifiers to match actually supported versions (3.10-3.12)
- black and ruff target-version to py310 (matching requires-python)

Author: kephale

.github/workflows/test_and_deploy.yml

@@ -26,10 +26,10 @@ jobs:
         python-version: ['3.10', '3.11', '3.12']
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
 
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
 
@@ -73,10 +73,10 @@ jobs:
       - uses: actions/checkout@v4
       - uses: tlambert03/setup-qt-libs@v1
       # Install dependencies
-      - name: Set up Python 3.9
+      - name: Set up Python 3.10
         uses: actions/setup-python@v5
         with:
-          python-version: 3.9
+          python-version: '3.10'
       - name: Install dependencies
         run: |
           pip install "PyOpenGL<3.1.7"
@@ -109,9 +109,9 @@ jobs:
     runs-on: ubuntu-22.04
     if: contains(github.ref, 'tags')
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
       - name: Set up Python
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v5
         with:
           python-version: "3.x"
       - name: Install dependencies

pyproject.toml

@@ -20,9 +20,9 @@ classifiers = [
     "Programming Language :: Python",
     "Programming Language :: Python :: 3",
     "Programming Language :: Python :: 3 :: Only",
-    "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 :: Scientific/Engineering :: Image Processing",
 ]
 requires-python = ">=3.10"
@@ -86,7 +86,7 @@ write_to = "src/surforama/_version.py"
 
 [tool.black]
 line-length = 79
-target-version = ['py38', 'py39', 'py310']
+target-version = ['py310', 'py311', 'py312']
 
 
 [tool.ruff]
@@ -132,5 +132,5 @@ exclude = [
     "*_vendor*",
 ]
 
-target-version = "py38"
+target-version = "py310"
 fix = true