CI: Auto-apply black formatting

.github/workflows/black.yml

@@ -0,0 +1,37 @@
+name: black
+
+on:
+  pull_request:
+    paths:
+      - '**.py'
+
+defaults:
+  run:
+    shell: bash
+
+jobs:
+  black:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+      with:
+        ref: ${{ github.head_ref }}
+    - name: Setup Python
+      uses: actions/setup-python@v4
+      with:
+        python-version: 3.x
+    - name: Install black
+      run: |
+        python -m pip install --upgrade pip
+        pip install black
+    - name: Version
+      run: |
+        python --version
+        black --version
+    - name: Run black
+      run: |
+        black xbout
+        black docs
+    - uses: stefanzweifel/git-auto-commit-action@v4
+      with:
+        commit_message: "Apply black formatting"

.github/workflows/master.yml

@@ -89,21 +89,3 @@ jobs:
   #    run: |
   #      pip install flake8
   #      flake8
-
-
-  black:
-
-    runs-on: ubuntu-latest
-    if: always()
-
-    steps:
-    - uses: actions/checkout@v2
-    - name: Set up Python
-      uses: actions/setup-python@v1
-    - name: Install dependencies
-      run: |
-        python -m pip install --upgrade pip
-    - name: Check formatting with black
-      run: |
-        pip install black
-        black --check .

.github/workflows/pythonpackage.yml

@@ -88,21 +88,3 @@ jobs:
   #    run: |
   #      pip install flake8
   #      flake8
-
-
-  black:
-
-    runs-on: ubuntu-latest
-    if: always()
-
-    steps:
-    - uses: actions/checkout@v2
-    - name: Set up Python
-      uses: actions/setup-python@v1
-    - name: Install dependencies
-      run: |
-        python -m pip install --upgrade pip
-    - name: Check formatting with black
-      run: |
-        pip install black
-        black --check .