fix tests on node < 14

Author: mydea

.github/workflows/build.yml

@@ -395,6 +395,7 @@ jobs:
           NODE_VERSION: ${{ matrix.node }}
         run: |
           [[ $NODE_VERSION == 8 ]] && yarn add --dev --ignore-engines --ignore-scripts --ignore-workspace-root-check [email protected]
+          [[ $NODE_VERSION < 14 ]] && yarn add --dev --ignore-engines --ignore-scripts --ignore-workspace-root-check [email protected]
           yarn test-ci
       - name: Compute test coverage
         uses: codecov/codecov-action@v3