[Go] Fix to allow duplicate key for provider (#16543)

internal/service/model_service.go

@@ -116,6 +116,14 @@ func (m *ModelProviderService) AddModelProvider(providerName, userID string) (co
 
 	tenantID := tenants[0].TenantID
 
+	existing, err := m.modelProviderDAO.GetByTenantIDAndProviderName(tenantID, providerName)
+	if err != nil && !errors.Is(err, gorm.ErrRecordNotFound) {
+		return common.CodeServerError, err
+	}
+	if existing != nil {
+		return common.CodeSuccess, nil
+	}
+
 	providerID := utility.GenerateToken()
 
 	tenantModelProvider := &entity.TenantModelProvider{