Fix bug with missing require in email-deliveries script

[mitchellhenke]

🛠 Summary of changes

The script makes use of #present? and fails without the require:

/Users/mitchellehenke/projects/identity-idp/lib/reporting/cloudwatch_client.rb:231:in `slice_time_range': undefined method `present?' for nil:NilClass (NoMethodError)

      if time_slices.present?
                    ^^^^^^^^^
        from /Users/mitchellehenke/projects/identity-idp/lib/reporting/cloudwatch_client.rb:64:in `fetch'
        from bin/oncall/email-deliveries:91:in `block in query_data'
        from /Users/mitchellehenke/projects/identity-idp/lib/reporting/unknown_progress_bar.rb:24:in `wrap'
        from bin/oncall/email-deliveries:90:in `query_data'
        from bin/oncall/email-deliveries:60:in `run'
        from bin/oncall/email-deliveries:150:in `<main>'

[zachmargolis]

Good catch! LGTM