ci: use Node.js 15

Author: coderbyheart

.github/workflows/build-and-release.yaml

@@ -10,10 +10,10 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v1
-      - uses: actions/setup-node@v1
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v2
         with:
-          node-version: "14.x"
+          node-version: "15.x"
       - name: Keep npm cache around to speed up installs
         uses: actions/cache@v1
         with: