Drop support for Node.js 8, 10. Add 16

See https://endoflife.date/nodejs

Author: ashwinvis

.github/workflows/nodejs.yml

@@ -16,10 +16,9 @@ jobs:
         os:
           - ubuntu-latest
         node_version:
-          - 8
-          - 10
           - 12
           - 14
+          - 16
         include:
           - os: windows-latest
             node_version: 14

package.json

@@ -10,7 +10,7 @@
   "license": "Apache-2.0",
   "homepage": "https://github.com/instant-markdown/instant-markdown-d",
   "engines": {
-    "node": ">=8.0.0"
+    "node": ">=12.0.0"
   },
   "main": "./src/cli.js",
   "preferGlobal": "true",