Align project files with CodeHarbor

Since both projects are developed together and by the same team, we also want to have the same code structure and utility methods available in both projects. Therefore, this commit changes many files, but without a functional change.

spec/controllers/codeharbor_links_controller_spec.rb

@@ -2,7 +2,7 @@
 
 require 'rails_helper'
 
-describe CodeharborLinksController do
+RSpec.describe CodeharborLinksController do
   render_views
 
   let(:user) { create(:teacher) }
@@ -44,14 +44,13 @@ describe CodeharborLinksController do
     context 'with invalid params' do
       let(:params) { {push_url: '', check_uuid_url: '', api_key: ''} }
 
+      before { post_request }
+
       it 'does not create a codeharbor_link' do
         expect { post_request }.not_to change(CodeharborLink, :count)
       end
 
-      it 'redirects to user show' do
-        post_request
-        expect(response).to render_template(:new)
-      end
+      expect_template(:new)
     end
   end
 
@@ -79,14 +78,13 @@ describe CodeharborLinksController do
     context 'with invalid params' do
       let(:params) { {push_url: '', check_uuid_url: '', api_key: ''} }
 
+      before { put_request }
+
       it 'does not change codeharbor_link' do
         expect { put_request }.not_to(change { codeharbor_link.reload.attributes })
       end
 
-      it 'redirects to user show' do
-        put_request
-        expect(response).to render_template(:edit)
-      end
+      expect_template(:edit)
     end
   end