Remove legacy storage from pages API

In 14.0 the only way to use legacy storage will be
`use_legacy_storage` flag which actually disables API domain config
source.

So we can simply remove support for legacy storage in the API

app/models/pages/lookup_path.rb

@@ -26,7 +26,18 @@ module Pages
     end
 
     def source
-      zip_source || legacy_source
+      return unless deployment&.file
+
+      global_id = ::Gitlab::GlobalId.build(deployment, id: deployment.id).to_s
+
+      {
+        type: 'zip',
+        path: deployment.file.url_or_file_path(expire_at: 1.day.from_now),
+        global_id: global_id,
+        sha256: deployment.file_sha256,
+        file_size: deployment.size,
+        file_count: deployment.file_count
+      }
     end
 
     def prefix
@@ -46,32 +57,5 @@ module Pages
         project.pages_metadatum.pages_deployment
       end
     end
-
-    def zip_source
-      return unless deployment&.file
-
-      global_id = ::Gitlab::GlobalId.build(deployment, id: deployment.id).to_s
-
-      {
-        type: 'zip',
-        path: deployment.file.url_or_file_path(expire_at: 1.day.from_now),
-        global_id: global_id,
-        sha256: deployment.file_sha256,
-        file_size: deployment.size,
-        file_count: deployment.file_count
-      }
-    end
-
-    # TODO: remove support for legacy storage in 14.3 https://gitlab.com/gitlab-org/gitlab/-/issues/328712
-    # we support this till 14.3 to allow people to still use legacy storage if something goes very wrong
-    # on self-hosted installations, and we'll need some time to fix it
-    def legacy_source
-      return unless ::Settings.pages.local_store.enabled
-
-      {
-        type: 'file',
-        path: File.join(project.full_path, 'public/')
-      }
-    end
   end
 end

spec/models/pages/lookup_path_spec.rb

@@ -47,14 +47,7 @@ RSpec.describe Pages::LookupPath do
   describe '#source' do
     let(:source) { lookup_path.source }
 
-    it 'uses disk storage', :aggregate_failures do
-      expect(source[:type]).to eq('file')
-      expect(source[:path]).to eq(project.full_path + "/public/")
-    end
-
-    it 'return nil when local storage is disabled and there is no deployment' do
-      allow(Settings.pages.local_store).to receive(:enabled).and_return(false)
-
+    it 'returns nil' do
       expect(source).to eq(nil)
     end