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GH-45398: [CI][Dev][Ruby] Add Ruby lint (#45417)



### Rationale for this change

Multiple users are developing Ruby codes. Adding Ruby Lint helps keep the same style.

### What changes are included in this PR?

Add Ruby Lint. (Rubocop)

### Are these changes tested?

Yes.

### Are there any user-facing changes?

No.

* GitHub Issue: #45398

Lead-authored-by: Hiroyuki Sato <hiroysato@gmail.com>
Co-authored-by: Sutou Kouhei <kou@cozmixng.org>
Signed-off-by: Sutou Kouhei <kou@clear-code.com>