fix tests

app/models/project.rb

@@ -491,10 +491,12 @@ class Project < ActiveRecord::Base
     hooks.send(hooks_scope).each do |hook|
       hook.async_execute(data)
     end
+    if group
       group.hooks.send(hooks_scope).each do |hook|
         hook.async_execute(data)
       end
     end
+  end
 
   def execute_services(data, hooks_scope = :push_hooks)
     # Call only service hooks that are active for this scope

spec/services/test_hook_service_spec.rb

@@ -4,7 +4,7 @@ describe TestHookService do
   let (:user)        { create :user }
   let (:group)       { create :group }
   let (:project)     { create :project, group: group }
-  let (:project_hook)    { create :project_hook, project: project }
+  let (:project_hook){ create :project_hook, project: project }
   let (:group_hook)  { create :group_hook, group: group }