Bump node version of CI

Rokt33r · Rokt33r · commit 6f3d320c56d2 · 2020-11-02T08:54:52.000+09:00
diff --git a/.travis.yml b/.travis.yml
@@ -1,3 +1,3 @@
 language: node_js
 node_js:
-  - '10'
+  - '12'

-Original file line number
+Diff line change
@@ @@ -1,3 +1,3 @@ @@
 language: node_js
 node_js:
 -  - '10'
 +  - '12'