Align urgency for Projects::Ci::LintsController#show with other lint endpoints

Problem

The Projects::Ci::LintsController#show action is missing an urgency setting, while other lint endpoints use urgency :low.

File: app/controllers/projects/ci/lints_controller.rb:9

Current:

urgency :low, [:create]

Expected:

urgency :low, [:show, :create]

Why

• API lint endpoints (lib/api/lint.rb) both have urgency: :low
• The controller's #create action already has urgency :low

This inconsistency causes unnecessary error budget consumption for feature_category :pipeline_composition.