Fix EE override

This is needed since lib/api/internal.rb was changed to
lib/api/internal/base.rb in CE. The fact that the EE port didn't fail
CI reveals that there are no tests in EE for this functionality.

ee/changelogs/unreleased/mk-fix-lfs-authentication-url-ee.yml

+---
+title: Fix LFS authentication URL in EE
+merge_request: 16146
+author:
+type: fixed

ee/lib/ee/api/internal.rb

-# frozen_string_literal: true
-
-module EE
-  module API
-    module Internal
-      extend ActiveSupport::Concern
-
-      prepended do
-        helpers do
-          extend ::Gitlab::Utils::Override
-
-          override :lfs_authentication_url
-          def lfs_authentication_url(project)
-            project.lfs_http_url_to_repo(params[:operation])
-          end
-        end
-      end
-    end
-  end
-end

ee/lib/ee/api/internal/base.rb

+# frozen_string_literal: true
+
+module EE
+  module API
+    module Internal
+      module Base
+        extend ActiveSupport::Concern
+
+        prepended do
+          helpers do
+            extend ::Gitlab::Utils::Override
+
+            override :lfs_authentication_url
+            def lfs_authentication_url(project)
+              project.lfs_http_url_to_repo(params[:operation])
+            end
+          end
+        end
+      end
+    end
+  end
+end

lib/api/internal/base.rb

@@ -271,3 +271,5 @@ module API
     end
   end
 end
+
+API::Internal::Base.prepend_if_ee('EE::API::Internal::Base')