Change GitHub service integration token input to password

changelogs/unreleased/security-mask-gh-service-password.yml

+---
+title: Change GitHub service integration token input to password
+merge_request:
+author:
+type: security

ee/app/models/project_services/github_service.rb

@@ -38,7 +38,7 @@ class GithubService < Service
 
   def fields
     [
-      { type: 'text',
+      { type: 'password',
         name: "token",
         required: true,
         placeholder: "e.g. 8d3f016698e...",

ee/spec/features/projects/services/user_activates_github_spec.rb

@@ -39,6 +39,10 @@ describe 'User activates GitHub Service' do
       expect(page).to have_content('GitHub activated.')
     end
 
+    it 'renders a token field of type `password` for masking input' do
+      expect(find('#service_token')['type']).to eq('password')
+    end
+
     context 'with pipelines', :js do
       let(:pipeline) { create(:ci_pipeline) }
       let(:project) { create(:project, ci_pipelines: [pipeline])}