Fix more hound warnings

spec/models/link_spec.rb

@@ -1,15 +1,15 @@
-require 'rails_helper'
+require "rails_helper"
 
 describe Link do
   let(:action) { build :dashboard_action }
 
-  it 'is invalid when label is blank' do
-    link = build(:link, linkable: action, label: '')
+  it "is invalid when label is blank" do
+    link = build(:link, linkable: action, label: "")
     expect(link).not_to be_valid
   end
 
-  it 'is invalid when url is blank' do
-    link = build(:link, linkable: action, url: '')
+  it "is invalid when url is blank" do
+    link = build(:link, linkable: action, url: "")
     expect(link).not_to be_valid
   end
 end