Make sure we reflect on execution failure

[mhenrixon]

It will be useful for debugging like below:

SidekiqUniqueJobs.reflect do |on|
  on.duplicate do |item|
    keys = Sidekiq.redis(&:keys)

    Rails.logger.error(
      <<~EOS.squish
        Duplicate lock: #{item}. The following keys are present in redis: [#{keys.join(',')}]
      EOS
    )
  end

  on.execution_failed do |item|
    keys = Sidekiq.redis(&:keys)

    Rails.logger.error(
      <<~EOS.squish
        Failed to execute: #{item}. The following keys are present in redis: [#{keys.join(',')}]
      EOS
    )
  end
end

Signed-off-by: mhenrixon mikael@mhenrixon.com