build: add codecov task to CI actions (#6)

.github/workflows/ci.yml

@@ -92,3 +92,28 @@ jobs:
         run: |
           echo "## Tests result" >> $GITHUB_STEP_SUMMARY
           echo "✅ Passed" >> $GITHUB_STEP_SUMMARY
+
+  coverage:
+    needs: ["lint", "build"]
+    runs-on: "ubuntu-latest"
+    steps:
+      - name: "Check out the repo"
+        uses: "actions/checkout@v3"
+        with:
+          submodules: "recursive"
+
+      - name: "Install Foundry"
+        uses: "foundry-rs/foundry-toolchain@v1"
+
+      - name: "Generate the coverage report using the unit and the integration tests"
+        run: 'forge coverage --match-path "test/**/*.sol" --report lcov'
+
+      - name: "Upload coverage report to Codecov"
+        uses: "codecov/codecov-action@v3"
+        with:
+          files: "./lcov.info"
+
+      - name: "Add coverage summary"
+        run: |
+          echo "## Coverage result" >> $GITHUB_STEP_SUMMARY
+          echo "✅ Uploaded to Codecov" >> $GITHUB_STEP_SUMMARY