Rename contains_namespace to by_group_and_descendents

Ci::NamespaceMirror.contains_namespace can be confusing and we decided
to rename it.

app/models/ci/namespace_mirror.rb

@@ -6,7 +6,7 @@ module Ci
   class NamespaceMirror < ApplicationRecord
     belongs_to :namespace
 
-    scope :contains_namespace, -> (id) do
+    scope :by_group_and_descendants, -> (id) do
       where('traversal_ids @> ARRAY[?]::int[]', id)
     end
 
@@ -32,7 +32,7 @@ module Ci
       private
 
       def sync_children_namespaces!(namespace_id, traversal_ids)
-        contains_namespace(namespace_id)
+        by_group_and_descendants(namespace_id)
           .where.not(namespace_id: namespace_id)
           .update_all(
             "traversal_ids = ARRAY[#{sanitize_sql(traversal_ids.join(','))}]::int[] || traversal_ids[array_position(traversal_ids, #{sanitize_sql(namespace_id)}) + 1:]"

app/models/ci/runner.rb

@@ -101,7 +101,7 @@ module Ci
     }
 
     scope :belonging_to_group_or_project_descendants, -> (group_id) {
-      group_ids = Ci::NamespaceMirror.contains_namespace(group_id).select(:namespace_id)
+      group_ids = Ci::NamespaceMirror.by_group_and_descendants(group_id).select(:namespace_id)
       project_ids = Ci::ProjectMirror.by_namespace_id(group_ids).select(:project_id)
 
       group_runners = joins(:runner_namespaces).where(ci_runner_namespaces: { namespace_id: group_ids })

spec/models/ci/namespace_mirror_spec.rb

@@ -20,10 +20,10 @@ RSpec.describe Ci::NamespaceMirror do
   end
 
   context 'scopes' do
-    describe '.contains_namespace' do
+    describe '.by_group_and_descendants' do
       let_it_be(:another_group) { create(:group) }
 
-      subject(:result) { described_class.contains_namespace(group2.id) }
+      subject(:result) { described_class.by_group_and_descendants(group2.id) }
 
       it 'returns groups having group2.id in traversal_ids' do
         expect(result.pluck(:namespace_id)).to contain_exactly(group2.id, group3.id, group4.id)