drop support for ruby 2.6 and test jruby

[seuros]

Summary

We are currently testing support for Ruby 2.6 to ensure compatibility with JRuby. However, JRuby now supports versions 2.7 to 3.1. I think upgrading the support to at least Ruby 2.7, which is nearing its end-of-life. Or even go directly to 3.0.

@keithdoggett , I want to give some maintenance shot to the repos.
Can you enable ci for my pr ?

[keithdoggett]

Hey @seuros thank you for doing this and appreciate your help with the projects!

[keithdoggett]

@seuros this issue with jruby popped up on other RGeo gem's CIs. It seems like if we use jruby head there's some bug in an implementation and a loop doesn't work as expected. I didn't look into it too much but the failing CIs show where the bug is occuring.

I'm not too familiar with JRuby, but I might have some time to look into this issue in a few days.

[seuros]

@keithdoggett i can look into it.

ps : jruby is easy, you need to drink lot of coffee while doing ruby.

[keithdoggett]

@seuros thanks! I got busy this week but should have some time soon if you can't get around to it either.

[keithdoggett]

Hey @seuros checking back in on this. It appears there was a bug in jruby-9.4.0.0 that was causing the issue. I just tried locally with the latest version (9.4.2.0) and it works. Can you push or re-run the tests so we can ensure that it is working on the CI as well then we can merge everything.

Thanks!

[seuros]

Yes

[keithdoggett]

Thank you for the contribution @seuros

[seuros]

I have few more pr to open

[keithdoggett]

Awesome looking forward to it. If you need help with any of them let me know