Explicitly disable JavaScript with honeypot fields

These fields are hidden for users with a browser supporting CSS and is
only there to fool bots, so we're testing the case of an attack by bots
using browsers with no CSS support.

spec/system/proposals_spec.rb

@@ -392,7 +392,7 @@ describe "Proposals" do
     expect(page).to have_content I18n.l(Proposal.last.created_at.to_date)
   end
 
-  scenario "Create with invisible_captcha honeypot field" do
+  scenario "Create with invisible_captcha honeypot field", :no_js do
     author = create(:user)
     login_as(author)