lint yaml

lint yaml

diff --git a/.travis.yml b/.travis.yml
index ac8e1e2..210c1a4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,3 +1,4 @@
+---
 language: ruby
 cache: bundler
 sudo: false
@@ -6,7 +7,7 @@ rvm:
   - 2.4
   - 2.5
 before_install:
-   - gem install bundler
+  - gem install bundler
 services:
   - redis
   - memcached

GitHub sha: 873add62