.travis.yml in benchmark_driver-0.10.0 vs .travis.yml in benchmark_driver-0.10.1

@@ -1,7 +1,6 @@
 language: ruby
 rvm:
-  - 2.1.10
   - 2.2.8
   - 2.3.6
   - 2.4.3
   - 2.5.0
 cache: bundler