chore(ci): add Node v16 (#829)

Author: SimenB

.github/workflows/nodejs.yml

@@ -48,7 +48,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        node-version: [10.x, 12.x, 14.x, 15.x]
+        node-version: [10.x, 12.x, 14.x, 15.x, 16.x]
         eslint-version: [5, 6, 7]
     runs-on: ubuntu-latest