Upgrade Node.js to v12 on Travis CI

kossnocorp · kossnocorp · commit 10ac1625d42b · 2019-10-22T14:55:28.000+07:00
Node.js v12 transitions into LTS, so I think it makes sense to upgrade it.
diff --git a/.travis.yml b/.travis.yml
@@ -2,7 +2,7 @@ sudo: false
 dist: trusty
 language: node_js
 node_js:
-  - 10
+  - 12
 
 stages:
   - test
