.travis.yml in openssl-signature_algorithm-0.2.0 vs .travis.yml in openssl-signature_algorithm-0.3.0

@@ -1,8 +1,10 @@
 ---
+dist: bionic
 language: ruby
 cache: bundler
 rvm:
   - 2.7.0
   - 2.6.5
   - 2.5.7
+  - 2.4.9
 before_install: gem install bundler -v 2.1.4