Fix Rails/SaveBang Rubocop offenses for admin controllers

.rubocop_manual_todo.yml

@@ -177,9 +177,6 @@ Rails/SaveBang:
     - 'qa/qa/specs/features/ee/browser_ui/3_create/repository/pull_mirroring_over_http_spec.rb'
     - 'qa/qa/specs/features/ee/browser_ui/3_create/repository/pull_mirroring_over_ssh_with_key_spec.rb'
     - 'spec/controllers/abuse_reports_controller_spec.rb'
-    - 'spec/controllers/admin/impersonations_controller_spec.rb'
-    - 'spec/controllers/admin/runners_controller_spec.rb'
-    - 'spec/controllers/admin/services_controller_spec.rb'
     - 'spec/controllers/boards/issues_controller_spec.rb'
     - 'spec/controllers/groups/milestones_controller_spec.rb'
     - 'spec/controllers/groups/runners_controller_spec.rb'

changelogs/unreleased/issue-220040-fix-rails-savebang-admin-controllers.yml

+---
+title: Fix Rails/SaveBang Rubocop offenses for admin controllers
+merge_request: 57644
+author: Huzaifa Iftikhar @huzaifaiftikhar
+type: fixed

spec/controllers/admin/impersonations_controller_spec.rb

@@ -42,7 +42,7 @@ RSpec.describe Admin::ImpersonationsController do
         context "when the impersonator is not admin (anymore)" do
           before do
             impersonator.admin = false
-            impersonator.save
+            impersonator.save!
           end
 
           it "responds with status 404" do

spec/controllers/admin/runners_controller_spec.rb

@@ -125,7 +125,7 @@ RSpec.describe Admin::RunnersController do
 
   describe '#resume' do
     it 'marks the runner as active and ticks the queue' do
-      runner.update(active: false)
+      runner.update!(active: false)
 
       expect do
         post :resume, params: { id: runner.id }
@@ -140,7 +140,7 @@ RSpec.describe Admin::RunnersController do
 
   describe '#pause' do
     it 'marks the runner as inactive and ticks the queue' do
-      runner.update(active: true)
+      runner.update!(active: true)
 
       expect do
         post :pause, params: { id: runner.id }

spec/controllers/admin/services_controller_spec.rb

@@ -44,7 +44,7 @@ RSpec.describe Admin::ServicesController do
   describe "#update" do
     let(:project) { create(:project) }
     let!(:service_template) do
-      RedmineService.create(
+      RedmineService.create!(
         project: nil,
         active: false,
         template: true,