Fix Rails/SaveBang Rubocop offenses for requests module

.rubocop_manual_todo.yml

@@ -408,8 +408,6 @@ Rails/SaveBang:
     - 'spec/requests/api/jobs_spec.rb'
     - 'spec/requests/api/labels_spec.rb'
     - 'spec/requests/api/project_import_spec.rb'
-    - 'spec/requests/projects/cycle_analytics_events_spec.rb'
-    - 'spec/requests/users_controller_spec.rb'
 
 Rails/TimeZone:
   Enabled: true

spec/requests/projects/cycle_analytics_events_spec.rb

@@ -75,7 +75,7 @@ RSpec.describe 'value stream analytics events' do
 
     context 'with private project and builds' do
       before do
-        project.members.last.update(access_level: Gitlab::Access::GUEST)
+        project.members.last.update!(access_level: Gitlab::Access::GUEST)
       end
 
       it 'does not list the test events' do
@@ -100,7 +100,7 @@ RSpec.describe 'value stream analytics events' do
 
   def create_cycle
     milestone = create(:milestone, project: project)
-    issue.update(milestone: milestone)
+    issue.update!(milestone: milestone)
     mr = create_merge_request_closing_issue(user, project, issue, commit_message: "References #{issue.to_reference}")
 
     pipeline = create(:ci_empty_pipeline, status: 'created', project: project, ref: mr.source_branch, sha: mr.source_branch_sha, head_pipeline_of: mr)

spec/requests/users_controller_spec.rb

@@ -663,7 +663,7 @@ RSpec.describe UsersController do
       end
 
       context 'when a user changed their username' do
-        let(:redirect_route) { user.namespace.redirect_routes.create(path: 'old-username') }
+        let(:redirect_route) { user.namespace.redirect_routes.create!(path: 'old-username') }
 
         it 'returns JSON indicating a user by that username does not exist' do
           get user_exists_url 'old-username'
@@ -705,7 +705,7 @@ RSpec.describe UsersController do
       end
 
       context 'when a user changed their username' do
-        let(:redirect_route) { user.namespace.redirect_routes.create(path: 'old-username') }
+        let(:redirect_route) { user.namespace.redirect_routes.create!(path: 'old-username') }
 
         it 'returns JSON indicating a user by that username does not exist' do
           get user_suggests_url 'old-username'
@@ -755,19 +755,19 @@ RSpec.describe UsersController do
         end
 
         context 'when requesting a redirected path' do
-          let(:redirect_route) { user.namespace.redirect_routes.create(path: 'old-path') }
+          let(:redirect_route) { user.namespace.redirect_routes.create!(path: 'old-path') }
 
           it_behaves_like 'redirects to the canonical path'
 
           context 'when the old path is a substring of the scheme or host' do
-            let(:redirect_route) { user.namespace.redirect_routes.create(path: 'http') }
+            let(:redirect_route) { user.namespace.redirect_routes.create!(path: 'http') }
 
             # it does not modify the requested host and ...
             it_behaves_like 'redirects to the canonical path'
           end
 
           context 'when the old path is substring of users' do
-            let(:redirect_route) { user.namespace.redirect_routes.create(path: 'ser') }
+            let(:redirect_route) { user.namespace.redirect_routes.create!(path: 'ser') }
 
             it_behaves_like 'redirects to the canonical path'
           end
@@ -806,19 +806,19 @@ RSpec.describe UsersController do
         end
 
         context 'when requesting a redirected path' do
-          let(:redirect_route) { user.namespace.redirect_routes.create(path: 'old-path') }
+          let(:redirect_route) { user.namespace.redirect_routes.create!(path: 'old-path') }
 
           it_behaves_like 'redirects to the canonical path'
 
           context 'when the old path is a substring of the scheme or host' do
-            let(:redirect_route) { user.namespace.redirect_routes.create(path: 'http') }
+            let(:redirect_route) { user.namespace.redirect_routes.create!(path: 'http') }
 
             # it does not modify the requested host and ...
             it_behaves_like 'redirects to the canonical path'
           end
 
           context 'when the old path is substring of users' do
-            let(:redirect_route) { user.namespace.redirect_routes.create(path: 'ser') }
+            let(:redirect_route) { user.namespace.redirect_routes.create!(path: 'ser') }
 
             # it does not modify the /users part of the path
             # (i.e. /users/ser should not become /ufoos/ser) and ...