Ruby 2.0 is retired at Travis

hsbt · hsbt · commit 5045567e0697 · 2023-06-13T13:02:10.000+09:00
diff --git a/.travis.yml b/.travis.yml
@@ -1,7 +1,6 @@
 sudo: false
 language: ruby
 rvm:
-  - 2.0.0-p648
   - 2.1.10
   - 2.2.10
   - 2.3.8
