Suspend jruby temporarily

Author: JonRowe

.travis.yml

@@ -43,6 +43,10 @@ script: "script/run_build 2>&1"
 dist: trusty
 
 matrix:
+  # temporary
+  allow_failures:
+    rvm: jruby-head
+
   include:
     # Rails 6 builds
     - rvm: jruby-head