Fix expose status in Runners API

Fixes https://gitlab.com/gitlab-org/gitlab/-/issues/348438

Changelog: fixed

lib/api/entities/ci/runner.rb

@@ -14,7 +14,7 @@ module API
         expose :online?, as: :online
         # DEPRECATED
         # TODO Remove in %15.0 in favor of `status` for REST calls, see https://gitlab.com/gitlab-org/gitlab/-/issues/344648
-        expose :status, as: :deprecated_rest_status
+        expose :deprecated_rest_status, as: :status
       end
     end
   end

spec/requests/api/ci/runners_spec.rb

@@ -254,6 +254,7 @@ RSpec.describe API::Ci::Runners do
           expect(response).to have_gitlab_http_status(:ok)
           expect(json_response['description']).to eq(shared_runner.description)
           expect(json_response['maximum_timeout']).to be_nil
+          expect(json_response['status']).to eq("not_connected")
         end
       end