Enable `release_mr_issue_urls` flag by default

This commit updates the `release_mr_issue_urls` feature flag to be
enabled by default.

app/presenters/release_presenter.rb

@@ -82,7 +82,7 @@ class ReleasePresenter < Gitlab::View::Presenter::Delegated
   end
 
   def release_mr_issue_urls_available?
-    ::Feature.enabled?(:release_mr_issue_urls, project)
+    ::Feature.enabled?(:release_mr_issue_urls, project, default_enabled: true)
   end
 
   def release_edit_page_available?

changelogs/unreleased/nfriend-make-release_mr_issue_urls-enabled-by-default.yml

+---
+title: Enable issue and MR stat links on release progress review
+merge_request: 46910
+author:
+type: added

config/feature_flags/development/release_mr_issue_urls.yml

 ---
 name: release_mr_issue_urls
 introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/18727
-rollout_issue_url:
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/276619
 group: group::release management
 type: development
-default_enabled: false
+default_enabled: true