Promote github import and gitlab migration specs to reliable

qa/qa/specs/features/api/1_manage/import_github_repo_spec.rb

 # frozen_string_literal: true
 
 module QA
-  RSpec.describe 'Manage', :github, :requires_admin do
+  RSpec.describe 'Manage', :github, :requires_admin, :reliable do
     describe 'Project import' do
       let!(:api_client) { Runtime::API::Client.as_admin }
       let!(:group) { Resource::Group.fabricate_via_api! { |resource| resource.api_client = api_client } }

qa/qa/specs/features/browser_ui/1_manage/group/gitlab_migration_group_spec.rb

 # frozen_string_literal: true
 
 module QA
-  describe 'Manage', :requires_admin do
+  describe 'Manage', :requires_admin, :reliable do
     describe 'Gitlab migration' do
       let!(:admin_api_client) { Runtime::API::Client.as_admin }
       let!(:user) do