Add darker to github workflow; also update version of darker used in …

…pre-commit hook.

.github/workflows/darker.yml

@@ -0,0 +1,17 @@
+name: 🧹 Darker
+
+on: [push, pull_request]
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+      - uses: actions/setup-python@v4
+        with:
+          python-version: '3.8'
+      - uses: akaihola/[email protected]
+        with:
+          version: "1.7.2"  # defaults to same version, but can be modified

.github/workflows/tests.yml

@@ -15,7 +15,7 @@ jobs:
         python-version: ["3.8", "3.10"]
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
 
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v4

.pre-commit-config.yaml

@@ -39,9 +39,9 @@ repos:
 
 
   - repo: https://github.com/akaihola/darker
-    rev: 1.6.1
+    rev: 1.7.2
     hooks:
     -   id: darker
         args: [--isort]
         additional_dependencies:
-        -   isort~=5.9
+          - isort~=5.9