ci: Add mypy linting for CI scripts

.github/workflows/script_lint.yml

@@ -21,4 +21,10 @@ jobs:
       - name: flake8 Lint
         uses: py-actions/flake8@v2
         with:
-           path: "common/CI"
+           path: common/CI
+      - name: mypy lint
+        uses: jpetrucciani/mypy-check@master
+        with:
+          path: common/CI
+          python_version: "3.10"
+          requirements: types-PyYAML

.gitignore

@@ -9,3 +9,6 @@
 common/Go/yabi/yabi
 common/Go/ypkg/ypkg-tools
 common/switch_repo_domains
+
+# Python caches
+.mypy_cache

.mypy.ini

@@ -0,0 +1,2 @@
+[mypy]
+strict = True