The move unused budget recommendation.

[Proto definition ![GitHub](https://developers.google.com/site-assets/logo-github.svg)](https://github.com/googleapis/googleapis/blob/master/google/ads/googleads/v26/resources/recommendation.proto)

| Fields ||
|---|---|
| ## `budget_recommendation` | `https://developers.google.com/google-ads/api/reference/rpc/v26/Recommendation.CampaignBudgetRecommendation` Output only. The recommendation for the constrained budget to increase. |
| ## `excess_campaign_budget` | `string` Output only. The excess budget's resource_name. |