Add Ruby Sydney - August 2025 (#1152)

Co-authored-by: marcoroth <6411752+marcoroth@users.noreply.github.com>

Author: github-actions[bot]

_data/meetups.yml

@@ -7223,6 +7223,13 @@
   end_time: 22:00:00 EDT
   url: https://www.meetup.com/phillyrb/events/307185647
 
+- name: Ruby on Rails Oceania Sydney - Ruby Sydney - August 2025 EDITION
+  location: Sydney, Australia
+  date: 2025-08-12
+  start_time: 18:00:00 AEST
+  end_time: 20:00:00 AEST
+  url: https://www.meetup.com/ruby-on-rails-oceania-sydney/events/310332015
+
 - name: RubyJax - Open Hax August 2025
   location: Jacksonville, FL
   date: 2025-08-12