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GH-35589: [Ruby] Add support or JRuby (#44346)

### Rationale for this change

JRuby is a Ruby implementation. It's based on Java. We have the Java implementation. So we can use it for JRuby.

### What changes are included in this PR?

This is not a complete support. This just can create int8 and int32 arrays by using the Java implementation not the C++ implementation. We can improve this step by step.

Note that we can build gem for JRuby but we'll not release it for now. We need to build our gems as artifacts by CI in release process and publish approved gems after release vote. If we use the current "gem build && gem push" for JRuby gems, we need JRuby on release. It's not desired because it increases release complexity.

### Are these changes tested?

Yes but only a few tests are only passed for now.

### Are there any user-facing changes?

Yes.
* GitHub Issue: #35589

Authored-by: Sutou Kouhei <kou@clear-code.com>
Signed-off-by: Sutou Kouhei <kou@clear-code.com>