Add OETH DApp Linter to CI

.github/workflows/defi.yml

@@ -156,6 +156,25 @@ jobs:
       - run: yarn prettier:check
         working-directory: ./dapp
 
+  dapp-oeth-lint:
+    name: "OETH DApp Linter"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Use Node.js
+        uses: actions/setup-node@v2
+        with:
+          node-version: "16.x"
+          cache: "yarn"
+          cache-dependency-path: dapp-oeth/yarn.lock
+
+      - run: yarn install --frozen-lockfile
+        working-directory: ./dapp-oeth
+
+      - run: yarn prettier:check
+        working-directory: ./dapp-oeth
+
   slither:
     name: "Slither"
     # As long as we need Python 3.6 here in the test, we can only use up to Ubuntu 20.