.travis.yml in viabtc-0.4.0 vs .travis.yml in viabtc-1.0.0

@@ -1,10 +1,10 @@
 ---
-sudo: false
 language: ruby
-cache: bundler
 rvm:
-  - 2.6.1
-  - 2.5.3
-  - 2.4.5
-  - 2.3.8
-before_install: gem install bundler -v 1.17.1
+  - 2.6.3
+  - 2.5.5
+  - 2.4.6
+before_install:
+  - 'gem update --system'
+  - 'gem --version'
+  - 'gem install bundler'