Fix and cleanup helper specs

ee/spec/helpers/ee/projects/security/api_fuzzing_configuration_helper_spec.rb

@@ -11,15 +11,18 @@
   let(:ci_variables_documentation_path) { help_page_path('ci/variables/README') }
   let(:project_ci_settings_path) { project_settings_ci_cd_path(project) }
+  subject { helper.api_fuzzing_configuration_data(project) }
+
+  before do
+    allow(helper).to receive(:current_user).and_return(user)
+  end
+
   describe '#api_fuzzing_configuration_data' do
-    context 'as a developer' do
+    context 'user without set_pipeline_variables policy' do
       before do
-        helper.instance_variable_set(:@current_user, user)
         allow(helper).to receive(:can?).with(user, :set_pipeline_variables, project).and_return(true)
       end
-      subject { helper.api_fuzzing_configuration_data(project) }
-
       it {
         is_expected.to eq(
           full_path: full_path,
@@ -32,14 +35,11 @@
       }
     end
-    context 'as a maintainer' do
+    context 'user with set_pipeline_variables policy' do
       before do
-        helper.instance_variable_set(:@current_user, user)
         allow(helper).to receive(:can?).with(user, :set_pipeline_variables, project).and_return(false)
       end
-      subject { helper.api_fuzzing_configuration_data(project) }
-
       it {
         is_expected.to eq(
           full_path: full_path,