Remove unused specs.

spec/features/issues_spec.rb

@@ -136,16 +136,6 @@ describe 'Issues', feature: true do
     end
   end
 
-  describe 'Time tracking slash commands', focus: true, js: true do
-    before do
-      issue = create(:issue, author: @user, assignee: @user, project: project)
-      project.team << [@user, :developer]
-      visit namespace_project_issue_path(project.namespace, project, issue)
-    end
-
-    it_behaves_like 'issuable time tracker'
-  end
-
   describe 'Issue info' do
     it 'excludes award_emoji from comment count' do
       issue = create(:issue, author: @user, assignee: @user, project: project, title: 'foobar')