actions: Use kiwicom/black image

To avoid waiting for the black package to be installed every time
schemathesis · Sep 13, 2019 · e820c0e · e820c0e
1 parent 282d046
commit e820c0e
Showing 1 changed file with 2 additions and 4 deletions.
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
@@ -8,11 +8,9 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@master
-    - uses: actions/setup-python@v1
+    - uses: docker://kiwicom/black
       with:
-        python-version: '3.7'
-    - run: pip install black
-    - run: black --check --diff .
+        args: black --check --diff .
 
   pylint:
     name: pylint