add workflow to lint workflow files

.github/actionlint-matcher.json

@@ -0,0 +1,17 @@
+{
+    "problemMatcher": [
+        {
+            "owner": "actionlint",
+            "pattern": [
+                {
+                    "regexp": "^(?:\\x1b\\[\\d+m)?(.+?)(?:\\x1b\\[\\d+m)*:(?:\\x1b\\[\\d+m)*(\\d+)(?:\\x1b\\[\\d+m)*:(?:\\x1b\\[\\d+m)*(\\d+)(?:\\x1b\\[\\d+m)*: (?:\\x1b\\[\\d+m)*(.+?)(?:\\x1b\\[\\d+m)* \\[(.+?)\\]$",
+                    "file": 1,
+                    "line": 2,
+                    "column": 3,
+                    "message": 4,
+                    "code": 5
+                }
+            ]
+        }
+    ]
+}

.github/workflows/lint-actions.yml

@@ -0,0 +1,29 @@
+name: Lint workflows
+
+on:
+  push:
+    paths:
+      - ".github/workflows/*"
+
+env:
+  GO_VERSION: "1.19"
+
+jobs:
+  lint-workflows:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+
+      - name: Install Go
+        uses: actions/setup-go@v3
+        with:
+          go-version: ${{ env.GO_VERSION }}.x
+          check-latest: true
+          cache: true
+
+      - name: Lint workflow files
+        run: |
+          echo "::add-matcher::.github/actionlint-matcher.json"
+          go install github.com/rhysd/actionlint/cmd/actionlint@latest
+          actionlint

.github/workflows/vuln.yml

@@ -1,4 +1,4 @@
-name: Vuln
+name: Vulnerability scan
 
 on:
   push: