[DRE-maint] Bug#1027296: ruby3.0: do not release with bookworm

[Sebastian Ramacher]

Source: ruby3.0
Version: 3.0.4-8
Severity: serious
X-Debbugs-Cc: sramacher at debian.org

Following the transition to ruby3.1 as only supported ruby version,
let's get ruby3.0 removed from bookworm.

Cheers
-- 
Sebastian Ramacher