Set Scala version

Atry · Atry · commit a8516803dac6 · 2019-04-28T09:48:16.000+08:00
diff --git a/.travis.yml b/.travis.yml
@@ -7,6 +7,9 @@ addons:
 
 language: scala
 
+scala:
+  - 2.12.8
+
 jdk:
   - oraclejdk8
 
