travis: enable go v1.12

yadvr · yadvr · commit 359249e970be · 2019-06-25T16:52:08.000+05:30
Signed-off-by: Rohit Yadav &lt;rohit.yadav@shapeblue.com&gt;
diff --git a/.travis.yml b/.travis.yml
@@ -18,10 +18,7 @@
 sudo: false
 language: go
 go:
-  - 1.11.x
+  - 1.12
 
 script:
   - make all
-
-env:
-  - GO111MODULE=on
