Fix random title with trailing spaces

When the generated title for a dashboard action ended with a space, the
action `click_link(feature.title)` failed because the link shown in the
HTML ignores the trailing spaces.

Using `strip` solves the problem. Not the most elegant solution, though;
ideally we'd generate a better title.

spec/factories/proposals.rb

@@ -132,7 +132,7 @@ FactoryBot.define do
   end
 
   factory :dashboard_action, class: "Dashboard::Action" do
-    title { Faker::Lorem.sentence[0..79] }
+    title { Faker::Lorem.sentence[0..79].strip }
     description { Faker::Lorem.sentence }
     link { nil }
     request_to_administrators { true }