Merge pull request #677 from aycabta/use-jruby-9.2.4.1

Use JRuby 9.2.4.1

Author: aycabta

.travis.yml

@@ -9,7 +9,7 @@ rvm:
   - 2.5.3
   - ruby-head
   - jruby-9.1.17.0
-  - jruby-9.2.4.0
+  - jruby-9.2.4.1
 env:
   global:
     NOBENCHMARK=1
@@ -18,4 +18,4 @@ matrix:
   allow_failures:
     - rvm: ruby-head
     - rvm: jruby-9.1.17.0
-    - rvm: jruby-9.2.4.0
+    - rvm: jruby-9.2.4.1