Get rid of old code

app/models/api_user.rb

@@ -10,8 +10,6 @@ class ApiUser < User
   validates :username, :password, :registrar, presence: true
   validates :username, uniqueness: true
 
-  before_save :create_crt, if: -> (au) { au.csr_changed? }
-
   attr_accessor :registrar_typeahead
 
   def ability
@@ -30,28 +28,5 @@ class ApiUser < User
   def queued_messages
     registrar.messages.queued
   end
-
-  def create_crt
-    csr_file = Tempfile.new('client_csr')
-    csr_file.write(csr)
-    csr_file.rewind
-
-    crt_file = Tempfile.new('client_crt')
-    _out, err, _st = Open3.capture3("openssl ca -keyfile #{APP_CONFIG['ca_key_path']} \
-    -cert #{APP_CONFIG['ca_cert_path']} \
-    -extensions usr_cert -notext -md sha256 \
-    -in #{csr_file.path} -out #{crt_file.path} -key '#{APP_CONFIG['ca_key_password']}' -batch")
-
-    if err.match(/Data Base Updated/)
-      crt_file.rewind
-      self.crt = crt_file.read
-      return true
-    else
-      errors.add(:base, I18n.t('failed_to_create_certificate'))
-      logger.error('FAILED TO CREATE CLIENT CERTIFICATE')
-      logger.error(err)
-      return false
-    end
-  end
 end
 # rubocop: enable Metrics/ClassLength