ASCENT-07: A Randomized, Open-label, Phase 3 Study of Sacituzumab Govitecan Versus Treatment of Physician’s Choice in Patients With Hormone Receptor-Positive (HR+)/Human Epidermal Growth Factor Receptor 2 Negative (HER2−) (HER2 IHC0 or HER2-low [IHC 1+, IHC 2+/ISH−]) Inoperable, Locally Advanced, or Metastatic Breast Cancer and Have Received Endocrine Therapy