arrow

GH-38300: [Dev][Docs] Update dev/README.md for the current merge_arrow_pr.py (#38301)

### Rationale for this change

dev/README.md is outdated.

### What changes are included in this PR?

* Don't require `arrow` remote
* Remove ARROW Jira related documents

### Are these changes tested?

No.

### Are there any user-facing changes?

No.
* Closes: #38300

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