Upgrade Node 15.x to 18.x

Node 15.x not available for Mac. Trying out 18.x, which itself is already in maintenance mode.

.github/workflows/build.yml

@@ -15,7 +15,7 @@ jobs:
           - '3.9'
           - '3.10'
         node-version:
-          - '15.x'
+          - '18.x'
     runs-on: ${{ matrix.os }}
     steps:
     - uses: actions/checkout@v2
@@ -50,7 +50,7 @@ jobs:
     - name: Build wheel
       run: python setup.py bdist_wheel
     - name: Upload wheels as artifacts
-      uses: actions/upload-artifact@v2
+      uses: actions/upload-artifact@v4
       if: ${{ runner.os == 'Linux' && matrix.python-version == '3.9' }}
       with:
         name: python-packages