Enable pages_serve_from_deployments feature flag by default

Signed-off-by: Balasankar "Balu" C <balasankarc@autistici.org>

app/models/pages/lookup_path.rb

@@ -41,7 +41,7 @@ module Pages
 
     def deployment
       strong_memoize(:deployment) do
-        next unless Feature.enabled?(:pages_serve_from_deployments, project)
+        next unless Feature.enabled?(:pages_serve_from_deployments, project, default_enabled: true)
 
         project.pages_metadatum.pages_deployment
       end

changelogs/unreleased/281178-pages-serve-from-deployments-configuration.yml

+---
+title: Enable pages_serve_from_deployments FF by default
+merge_request: 48974
+author:
+type: changed

config/feature_flags/development/pages_serve_from_deployments.yml

@@ -5,4 +5,4 @@ rollout_issue_url: https://gitlab.com/gitlab-com/gl-infra/production/-/issues/29
 milestone: '13.6'
 type: development
 group: group::Release Management
-default_enabled: false
+default_enabled: true