Log Message:
devel/ruby-redmine51: update to 5.1.1

pkgsrc change: depends on net/ruby-net-{imap,pop,smtp} with ruby31.

5.1.1 (2023-11-27)

[Database]

* Defect #39437: MySQL / MariaDB issue nested set deadlocks and consistency

* Defect #39443: Invalid statement query error on MSSQL when role filter is
  used in issues query

* Patch #39737: Support MySQL 8

[Email notifications]

* Defect #39553: Mention notification is not sent
  (MENTION_PATTERN / LINKS_RE inconsistency)

[Filters]

* Defect #39714: Query grouping filter not working for custom field
  relations

[Gems support]

* Defect #39576: `rake yard` does not work with Ruby >= 3.2

[Issues]

* Defect #39521: Mention autocomplete not displaying for users
  without "Edit issues" permission

[PDF export]

* Defect #39534: Error (undefined method) in issue list PDF export

[Text formatting]

* Defect #38852: ## issue syntax is not kept when selecting an issue from
  the inline autocomplete

[Translations]

* Patch #39513: Bulgarian translation update for 5.1-stable
* Patch #39551: Simplified Chinese translation update for 5.1-stable