Fix project import data spec

We need a persisted user for the project because it is used in some
specs

ee/spec/models/project_import_data_spec.rb

@@ -5,9 +5,11 @@ require 'spec_helper'
 RSpec.describe ProjectImportData do
   using RSpec::Parameterized::TableSyntax
 
+  let_it_be(:user) { create(:user) }
+
   let(:import_url) { 'ssh://example.com' }
   let(:import_data_attrs) { { auth_method: 'ssh_public_key' } }
-  let(:project) { build(:project, :mirror, import_url: import_url, import_data_attributes: import_data_attrs) }
+  let(:project) { build(:project, :mirror, creator: user, import_url: import_url, import_data_attributes: import_data_attrs) }
 
   subject(:import_data) { project.import_data }
 
@@ -33,8 +35,6 @@ RSpec.describe ProjectImportData do
   end
 
   describe '#ssh_known_hosts_verified_by' do
-    let(:user) { project.owner }
-
     subject { import_data.ssh_known_hosts_verified_by }
 
     it 'is a user when ssh_known_hosts_verified_by_id is a valid id' do

ee/spec/models/project_spec.rb

@@ -270,11 +270,11 @@ RSpec.describe Project do
   describe 'setting up a mirror' do
     context 'when new project' do
       it 'creates import_state and sets next_execution_timestamp to now' do
-        project = build(:project, :mirror)
+        project = build(:project, :mirror, creator: create(:user))
 
         Timecop.freeze do
           expect do
-            project.save
+            project.save!
           end.to change { ProjectImportState.count }.by(1)
 
           expect(project.import_state.next_execution_timestamp).to be_like_time(Time.current)

spec/helpers/storage_helper_spec.rb

@@ -22,11 +22,12 @@ RSpec.describe StorageHelper do
   end
 
   describe "#storage_counters_details" do
-    let(:namespace) { create :namespace }
-    let(:project) do
+    let_it_be(:namespace) { create(:namespace) }
+    let_it_be(:project) do
       create(:project,
              namespace: namespace,
              statistics: build(:project_statistics,
+                               namespace:            namespace,
                                repository_size:      10.kilobytes,
                                wiki_size:            10.bytes,
                                lfs_objects_size:     20.gigabytes,

spec/models/namespace_spec.rb

@@ -175,12 +175,13 @@ RSpec.describe Namespace do
   end
 
   describe '.with_statistics' do
-    let(:namespace) { create :namespace }
+    let_it_be(:namespace) { create(:namespace) }
 
     let(:project1) do
       create(:project,
              namespace: namespace,
              statistics: build(:project_statistics,
+                               namespace:            namespace,
                                repository_size:      101,
                                wiki_size:            505,
                                lfs_objects_size:     202,
@@ -193,6 +194,7 @@ RSpec.describe Namespace do
       create(:project,
              namespace: namespace,
              statistics: build(:project_statistics,
+                               namespace:            namespace,
                                repository_size:      10,
                                wiki_size:            50,
                                lfs_objects_size:     20,