Use the latest Rubies on Travis CI

[koic]

These Rubies has been released.

https://www.ruby-lang.org/en/news/2019/04/01/ruby-2-4-6-released/
https://www.ruby-lang.org/en/news/2019/04/17/ruby-2-6-3-released/

[siegy22]

How about we just specify the minor version? 😄 like 2.4 and 2.6

[koic]

I'm not sure whether to behave with the expected tiny version if I omit the tiny version.
rails/rails#29232 (comment)

[siegy22]

The only difference here is, it will automatically pick the latest 2.x version without having to bump it with every patch level release in the travis file. I'd assume it's fair to pin only the minor version and if a tests starts failing because of that automatic update, then I would be concerned about the ruby release itself and not the compatibility with this gem. 😄

In general there are two approaches:
1: Bump patch version if a ruby version was released

2: Specify only the minor version; if the build fails because of the latest version, pin it down and fix it. and then re-pin to the minor version to use automatically the newest version.

I don't wanna blame you or anything it's just a step that someone has do to manually, and that just generates more work for a gem to maintain.

[koic]

I see. It seems to be able to target the entire .travis.yml configuration in this repository. So I wait for the maintainer's decision. Thank for your explanation.

[cadwallion]

Apologies for the delayed response on this. I'm content with merging this in as-is for now and we'll bump up manually as releases come out.