Slim down the gem section for Solid

They come as a pair, no need to overexplain

Author: dhh

railties/lib/rails/generators/rails/app/templates/Gemfile.tt

@@ -13,13 +13,9 @@ source "https://rubygems.org"
 gem "tzinfo-data", platforms: %i[ <%= bundler_windows_platforms %> jruby ]
 <% unless options.skip_solid? -%>
 
-# Use the database-backed Solid Cache adapter for Rails.cache [https://github.com/rails/solid_cache]
+# Use the database-backed adapters for Rails.cache, Active Job, and Action Cable
 gem "solid_cache"
-
-# Use the database-backed Solid Queue adapter for Active Job [https://github.com/rails/solid_queue]
 gem "solid_queue"
-
-# Use the database-backed Solid Cable adapter for Action Cable [https://github.com/rails/solid_cable]
 gem "solid_cable"
 <% end -%>
 <% if depend_on_bootsnap? -%>