Add reply-back action to org application info requests

[Ayudh-M]

Pull Request Checklist

• I’ve read the guidelines for contributing.
• I created a dedicated branch fix-18040-reply-back-button.
• I ran the relevant unit test(s) and got no failures.

Description — fix #18040

Added a Reply Back button near the bottom of the Information Requests conversation on the admin organization application detail page. The button reuses the existing Request More Info modal (#requestMoreInfoModal) and its existing POST handler.

This patch:

• adds a bottom-of-thread Reply Back button that opens the existing #requestMoreInfoModal
• mirrors existing disable logic (permission + status checks) used by the top Request Info action
• adds a small regression unit test to ensure the modal trigger exists twice (top + bottom) and the new label is present

No functional change beyond exposing the existing “request more info” action at the bottom of the conversation.

Fixes #18040

Testing

command	expected / observed
python -m pytest tests/unit/admin/test_organization_application_detail_template.py	passes
manual UI: admin org application detail → scroll to bottom of “Information Requests”	Reply Back present and opens Request More Info modal

[miketheman]

@Ayudh-M You might want to run make reformat , make lint, make translations locally to prevent the back-and-forth with CI.
https://warehouse.pypa.io/development/submitting-patches/#code