Timeout on a test project with Linux build and no error message, how to debug or show log output?

I have an ASP.NET Core open source project, I’m using travis for Linux build. It keeps failing due to timing out on a test project. It just times out and there are no error messages. The same repo is able to build and pass all tests against Windows and Mac OS with no problem, but Linux is not.

https://travis-ci.org/FanrayMedia/Fanray

I singled out to which test classes may cause the timeout, also tried to add Log info or debug statements, but I don’t know to you can debug or view the log output on Travis CI? Have others experience something like this or how do you solve it? Thank you!