chore(travis): remove test on node 6/8, add node 16

AoDev · AoDev · commit 8945b812083d · 2021-11-17T15:24:45.000+01:00
Note: the library works on node 6/8, just eslint won't.
diff --git a/.travis.yml b/.travis.yml
@@ -1,8 +1,7 @@
 language: node_js
 script: npm run lint && npm run test
 node_js:
-  - '6'
-  - '8'
   - '10'
   - '12'
   - '14'
+  - '16'
