Add backwards compatibility to Ruby 2.6

[scpike]

This removes use of the "anonymous block argument" feature which is only supported in Ruby 3.1+ so that the library stays backwards compatible to earlier ruby versions.

[deepakmahakale]

Can we get this pr merged. Current version breaks on ruby 2.7

[pacso]

@seejohnrun - what are your thoughts on this? Do we want to actively support version of Ruby / Rails which are end-of-life? If we do, where do we draw the line?

[scpike]

@seejohnrun - what are your thoughts on this? Do we want to actively support version of Ruby / Rails which are end-of-life? If we do, where do we draw the line?

I made the PR because I think it's helpful when gems support the versions of rubies their gemspecs allow. If you want to drop Ruby 2.x support explicitly, it'd still be nice for the latest version of the gem before that one to include this patch.

[pacso]

Yep - it's a fair comment.

I've updated the PR to pass against all of the versions back to Rails 6.1 and Ruby 2.6. I'll review it again in the morning when I'm not so tired and get it merged.