Keep TAGS_LIMIT in sync for TaggableQueries

This commit makes sure we keep in sync both area of the codebase
when dealing with tags limit for processing jobs.

spec/models/concerns/taggable_queries_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe TaggableQueries do
+  it 'keeps MAX_TAGS_IDS in sync with TAGS_LIMIT' do
+    expect(described_class::MAX_TAGS_IDS).to eq(Gitlab::Ci::Config::Entry::Tags::TAGS_LIMIT)
+  end
+end