Add step to copy .env file in CI workflow

Author: Aphyla

.github/workflows/test.yml

@@ -36,6 +36,11 @@ jobs:
           yarn build --sizes --skip test
         id: build
 
+      - name: Copy .env
+        run: |
+          cp .env.example .env
+        id: copy-env
+
       - name: Run Forge tests
         run: |
           yarn fast-test -vvv