NoMethodError: undefined method `each' for nil:NilClass

https://sentry.gitlab.net/gitlab/gitlabcom/issues/2692150/?referrer=gitlab_plugin

NoMethodError: undefined method `each' for nil:NilClass
  gitlab/github_import/importer/pull_requests_reviews_importer.rb:81:in `block in each_merge_request_to_import'
    page.objects.each do |review|
  gitlab/github_import/importer/pull_requests_reviews_importer.rb:103:in `block (2 levels) in each_review_page'
    yield(page, merge_request)
  gitlab/github_import/client.rb:119:in `each_page'
    yield Page.new(collection, page)
  gitlab/github_import/importer/pull_requests_reviews_importer.rb:100:in `block in each_review_page'
    client.each_page(collection_method, repo, merge_request.iid, options) do |page|
  activerecord (6.1.3.2) lib/active_record/relation/batches.rb:71:in `block (2 levels) in find_each'
...
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undefined method `each' for nil:NilClass