Remove pending specs for methods that dont exist (#1658)

* Remote spec for non-existent entry_classes helper method

This method no longer exists, and is handled by a local variable in a partial
instead.

* Remove spec for non-existent Account#ping! method

spec/helpers/stream_entries_helper_spec.rb

@@ -14,8 +14,4 @@ RSpec.describe StreamEntriesHelper, type: :helper do
       expect(helper.display_name(account)).to eq "Username"
     end
   end
-
-  describe '#entry_classes' do
-    pending
-  end
 end