update flex quickstart sample tagging

Author: srinjoyray

appengine/flexible/hello_world/Gemfile

@@ -18,7 +18,6 @@ source "https://rubygems.org"
 gem "sinatra"
 gem "webrick", "~> 1.8"
 
-# [END gae_flex_quickstart_dependencies]
 ruby "~>3.4"
 group :test do
   gem "rack-test"
@@ -28,3 +27,5 @@ end
 
 gem "puma", "~> 6.6"
 gem "rackup", "~> 2.2"
+
+# [END gae_flex_quickstart_dependencies]