ArgumentError: string contains null byte

This caused incident gitlab-com/gl-infra/production#2488 (closed) which was due to bot scanning, causing increased errors. No user impact but we should probably be handling the error.

https://sentry.gitlab.net/gitlab/gitlabcom/issues/1739196/?referrer=gitlab_plugin

ArgumentError: string contains null byte
  active_record/connection_adapters/postgresql/quoting.rb:21:in `escape_string'
    @connection.escape(s)
  active_record/connection_adapters/postgresql/quoting.rb:21:in `quote_string'
    @connection.escape(s)
  active_record/connection_adapters/abstract/quoting.rb:220:in `_quote'
    "'#{quote_string(value.to_s)}'"
  active_record/connection_adapters/postgresql/quoting.rb:144:in `_quote'
    super
  active_record/connection_adapters/abstract/quoting.rb:18:in `quote'
    _quote(value)
...
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ArgumentError: string contains null byte