Enable FF "tags_finder_gitaly" by default

Contributes to https://gitlab.com/gitlab-org/gitlab/-/issues/339741

`gitaly_` prefix is reserved for Gitaly related feature flags and
shouldn't be used here. I've renamed it.

Changelog: performance

app/models/repository.rb

@@ -732,7 +732,7 @@ class Repository
   end
 
   def tags_sorted_by(value)
-    return raw_repository.tags(sort_by: value) if Feature.enabled?(:gitaly_tags_finder, project, default_enabled: :yaml)
+    return raw_repository.tags(sort_by: value) if Feature.enabled?(:tags_finder_gitaly, project, default_enabled: :yaml)
 
     tags_ruby_sort(value)
   end

config/feature_flags/development/gitaly_tags_finder.yml → config/feature_flags/development/tags_finder_gitaly.yml

 ---
-name: gitaly_tags_finder
+name: tags_finder_gitaly
 introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/69101
 rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/339741
 milestone: '14.3'
 type: development
 group: group::source code
-default_enabled: false
+default_enabled: true

spec/models/repository_spec.rb

@@ -71,7 +71,7 @@ RSpec.describe Repository do
     let(:feature_flag) { true }
 
     before do
-      stub_feature_flags(gitaly_tags_finder: feature_flag)
+      stub_feature_flags(tags_finder_gitaly: feature_flag)
     end
 
     context 'name_desc' do