add blue check.

.github/workflows/lint-workflow.yml

@@ -17,9 +17,13 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
+        pip install blue
         pip install pylint
         pip install pylama
-        mypy
+        pip install mypy
+    - name: Check blue
+      run: |
+        blue . --check
     - name: Analysing the code with pylama
       run: |
         pylama --skip='tests/*'