.travis.yml in ndarmyserver_palindrome-0.2.0 vs .travis.yml in ndarmyserver_palindrome-0.2.1

@@ -2,6 +2,6 @@
 sudo: false
 language: ruby
 cache: bundler
 rvm:
   - 2.6.0
-before_install: gem install bundler -v 2.0.1
+before_install: gem install bundler -v 1.17.3