Check shell scripts using ShellCheck via reviewdog (#5)

https://github.com/reviewdog/action-shellcheck

https://www.shellcheck.net/

Author: johnboyes

.github/workflows/reviewdog.yml

@@ -21,9 +21,23 @@ jobs:
     name: runner / yamllint
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v1
+      - uses: actions/checkout@v2
       - name: yamllint
         uses: reviewdog/action-yamllint@v1
         with:
           github_token: ${{ secrets.github_token }}
           reporter: github-check
+
+  shellcheck:
+    name: runner / shellcheck
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: shellcheck
+        uses: reviewdog/action-shellcheck@v1
+        with:
+          github_token: ${{ secrets.github_token }}
+          reporter: github-check
+          path: "."
+          pattern: "*.sh"
+          exclude: "./.git/*"