build: Node.js@15.8

Author: dougwilson

.github/workflows/ci.yml

@@ -101,7 +101,7 @@ jobs:
           node-version: "14.15"
 
         - name: Node.js 15.x
-          node-version: "15.5"
+          node-version: "15.8"
 
     steps:
     - uses: actions/checkout@v2