Revert "tmp: bump node version"

This reverts commit e4069e1.

Author: cometkim

.github/workflows/ci.yml

@@ -82,7 +82,7 @@ jobs:
       - name: Use Node.js
         uses: actions/setup-node@v4
         with:
-          node-version: 20
+          node-version: 18
 
       - name: Copy exes to platform bin dirs
         run: node ./scripts/copyExes.js