build(deps): upgrade to node 15

Author: kollhof

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
     - name: setup nodejs
       uses: actions/setup-node@v1
       with:
-        node-version: 14.x
+        node-version: 15.x
 
     - name: install dependencies
       env: