Validate testcases workflow

.github/workflows/validate-testcases.yaml

@@ -0,0 +1,35 @@
+name: Validate testcases
+
+on: [push]
+
+permissions:
+  contents: read
+
+jobs:
+  checkout:
+    name: Checkout repositories
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout corpus repository
+        uses: actions/checkout@v4
+        with:
+          path: corpus
+      - name: Checkout validator repository
+        uses: actions/checkout@v4
+        with:
+          repository: E-ARK-Software/eark-validator
+          path: validator
+  build:
+    name: Build validator
+    runs-on: ubuntu-latest
+    steps:
+    - name: Set up Python 3.10
+      uses: actions/setup-python@v3
+      with:
+        python-version: "3.10"
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install .
+    - name: Check validator
+      run: ip-check