fix langchain tests trying to run on unsupported node (#4926)

Author: rochdev

.github/workflows/plugins.yml

@@ -567,7 +567,18 @@ jobs:
       PLUGINS: langchain
     steps:
       - uses: actions/checkout@v4
-      - uses: ./.github/actions/plugins/test
+      - uses: ./.github/actions/testagent/start
+      - uses: ./.github/actions/node/setup
+      - uses: ./.github/actions/install
+      - uses: ./.github/actions/node/18 # langchain doesn't support Node 16
+      - run: yarn test:plugins:ci
+        shell: bash
+      - uses: ./.github/actions/node/latest
+      - run: yarn test:plugins:ci
+        shell: bash
+      - uses: codecov/codecov-action@v3
+      - if: always()
+        uses: ./.github/actions/testagent/logs
 
   limitd-client:
     runs-on: ubuntu-latest