ci: add node@14 and remove v13 (#627)

Author: hiroppy

.github/workflows/nodejs.yml

@@ -55,15 +55,15 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, windows-latest, macos-latest]
-        node-version: [10.x, 12.x, 13.x]
+        node-version: [10.x, 12.x, 14.x]
         webpack-version: [latest, next]
         exclude:
           # See https://github.com/fsevents/fsevents/issues/314
           - os: macos-latest
             node-version: 12.x
             webpack-version: latest
           - os: macos-latest
-            node-version: 13.x
+            node-version: 14.x
             webpack-version: latest
 
     runs-on: ${{ matrix.os }}