Fix undefined method log_geo_deleted_event for MergeRequestDiff

app/models/merge_request_diff.rb

@@ -591,3 +591,5 @@ class MergeRequestDiff < ApplicationRecord
     end
   end
 end
+
+MergeRequestDiff.prepend_if_ee('EE::MergeRequestDiff')

ee/app/models/ee/merge_request_diff.rb

+# frozen_string_literal: true
+
+module EE
+  module MergeRequestDiff
+    def log_geo_deleted_event
+      # Keep empty for now. Should be addressed in future
+      # by https://gitlab.com/gitlab-org/gitlab/issues/33817
+    end
+  end
+end

ee/spec/models/ee/merge_request_diff_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe MergeRequestDiff do
+  it { is_expected.to respond_to(:log_geo_deleted_event) }
+end