Revert change to run unit test on node 18.

Author: taeold

.github/workflows/test.yaml

@@ -53,7 +53,6 @@ jobs:
         node-version:
           - 14.x
           - 16.x
-          - 18.x
     steps:
       - uses: actions/checkout@v1
       - uses: actions/setup-node@v1