Cleanup the conan endpoints concern

By moving it to the proper location

lib/api/conan_instance_packages.rb

@@ -4,7 +4,7 @@
 module API
   class ConanInstancePackages < ::API::Base
     namespace 'packages/conan/v1' do
-      include ConanPackageEndpoints
+      include ::API::Concerns::Packages::ConanEndpoints
     end
   end
 end

lib/api/conan_project_packages.rb

@@ -9,7 +9,7 @@ module API
 
     resource :projects, requirements: API::NAMESPACE_OR_PROJECT_REQUIREMENTS do
       namespace ':id/packages/conan/v1' do
-        include ConanPackageEndpoints
+        include ::API::Concerns::Packages::ConanEndpoints
       end
     end
   end