add separate CI pipeline for formal

.github/workflows/formal_verification.yml

@@ -0,0 +1,29 @@
+name: formal_verification
+on: [push]
+jobs:
+  all:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Install Manta from Source
+        run: |
+          pip install setuptools --upgrade
+
+          # omitting the following commmand causes the version of setuptools
+          # used by python to get confused, and it doesn't detect the name
+          # or version of the package from pyproject.toml - so the following
+          # workaround is used:
+          # https://github.com/pypa/setuptools/issues/3269#issuecomment-1254507377
+          export DEB_PYTHON_INSTALL_LAYOUT=deb_system
+
+          python3 -m pip install .
+
+      - name: Install oss-cad-suite
+        run: |
+          wget --no-verbose https://github.com/YosysHQ/oss-cad-suite-build/releases/download/2023-02-23/oss-cad-suite-linux-x64-20230223.tgz
+          tar -xzf oss-cad-suite-linux-x64-20230223.tgz
+          echo "$(pwd)/oss-cad-suite/bin" >> $GITHUB_PATH
+
+      - name: Run formal verification
+        run: make formal

.github/workflows/functional_simulation.yml

@@ -1,4 +1,4 @@
-name: functional_sim
+name: functional_simulation
 on: [push]
 jobs:
   all:
@@ -26,7 +26,4 @@ jobs:
           echo "$(pwd)/oss-cad-suite/bin" >> $GITHUB_PATH
 
       - name: Run functional simulations
-        run: make sim
-
-      - name: Run formal verification
-        run: make formal
+        run: make sim