Fix some broken specs

app/models/gpg_key.rb

@@ -119,7 +119,7 @@ class GpgKey < ActiveRecord::Base
   def generate_subkeys
     gpg_subkeys = Gitlab::Gpg.subkeys_from_key(key)
 
-    gpg_subkeys[primary_keyid].each do |subkey_data|
+    gpg_subkeys[primary_keyid]&.each do |subkey_data|
       subkeys.create!(keyid: subkey_data[:keyid], fingerprint: subkey_data[:fingerprint])
     end
   end

spec/factories/gpg_key_subkeys.rb

@@ -4,7 +4,7 @@ FactoryGirl.define do
   factory :gpg_key_subkey do
     gpg_key
 
-    keyid { gpg_key.subkeys.last.keyid }
-    fingerprint { gpg_key.subkeys.last.fingerprint }
+    sequence(:keyid) { |n| "keyid-#{n}" }
+    sequence(:fingerprint) { |n| "fingerprint-#{n}" }
   end
 end