chore: add GRE test to GitHub actions

.github/workflows/gre.yml

@@ -0,0 +1,27 @@
+name: Run GRE tests
+
+on:
+  push:
+    branches: [dev]
+  pull_request: {}
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        node-version: [16.x]
+
+    steps:
+      - uses: actions/checkout@v3
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v3
+        with:
+          node-version: ${{ matrix.node-version }}
+      - name: Install packages
+        run: yarn install --non-interactive --frozen-lockfile
+      - name: Build project
+        run: yarn build
+      - name: Run GRE tests
+        run: yarn test:gre

gre/test/fixture-projects/default-config/hardhat.config.ts

@@ -0,0 +1,8 @@
+module.exports = {
+  networks: {
+    mainnet: {
+      chainId: 1,
+      url: `https://mainnet.infura.io/v3/123456`,
+    },
+  },
+}