add separate ci for ffi tests

.github/workflows/test-ffi.yml

@@ -0,0 +1,41 @@
+name: Test FFI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  test:
+    runs-on: macos-latest
+
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+        - testname: "ffi:tests"
+
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          submodules: recursive
+
+      - name: Install Foundry
+        uses: foundry-rs/foundry-toolchain@v1
+
+      - name: Set up Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: "3.11"
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install pytest
+
+      - name: Install Halmos
+        run: pip install -e .
+
+      - name: Run pytest
+        run: pytest -v tests/test_halmos.py -k ${{ matrix.testname }} --halmos-options="--ffi -v -st --error-unknown --test-parallel --solver-parallel --solver-timeout-assertion 0"