Merge pull request rails#23929 from prathamesh-sonpatki/update-deprecation-message-for-app-namespace

Update deprecation message shown when tasks from rails namespace are run

Author: kaspth

railties/lib/rails/tasks/framework.rake

@@ -73,8 +73,8 @@ namespace :rails do
   %i(update template templates:copy update:configs update:bin).each do |task_name|
     task "#{task_name}" do
       ActiveSupport::Deprecation.warn(<<-MSG.squish)
-        Running #{task_name} with the rails: namespace is deprecated in favor of app.
-        Run e.g. bin/rails app:#{task_name} instead."
+        Running #{task_name} with the rails: namespace is deprecated in favor of app: namespace.
+        Run bin/rails app:#{task_name} instead.
       MSG
       Rake.application.invoke_task("app:#{task_name}")
     end