The error message given by the Travis build with Ruby 2.5 seems to be the one shown in [this issue](https://github.com/travis-ci/travis-ci/issues/8978), which is a duplicate of [this open issue](https://github.com/travis-ci/travis-ci/issues/8969). I have no idea why the JRuby build is failing. Suggestions are welcome.
The error message given by the Travis build with Ruby 2.5 seems to be the one shown in this issue, which is a duplicate of this open issue.
I have no idea why the JRuby build is failing. Suggestions are welcome.