Mocking EF in the wrong way

Ef Mock

namespace efsetp;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.ChangeTracking;
using Microsoft.EntityFrameworkCore.ChangeTracking.Internal;
using Microsoft.EntityFrameworkCore.Metadata;
using Moq;

public class Customer
{
    public int CustomerId { get; set; }
    public string Name { get; set; } = "";
}

public class CustomerRepository
{
    protected readonly DbContext DbContext;
    public CustomerRepository(DbContext dbContext)
    {
        DbContext = dbContext;
    }
    public virtual void Delete<TEntity>(TEntity entity)
    where TEntity: class
    {
        var entry = DbContext.Entry(entity);
        if (entry.State == EntityState.Detached)
        {
            DbContext.Attach(entity);
        }
        DbContext.Remove(entity);        
    }
}

public class UnitTest1
{

    [Fact]
    public void Delete_SomeEntityToRepository_CallsTheAddMethod_To_DbContext()
    {
        // Arrange
        var testObject = new Customer();

        var internalEntityEntry = GetInternalEntityEntry(testObject);

        var dbEntityEntryMock = new Mock<EntityEntry<Customer>>(internalEntityEntry);
        dbEntityEntryMock.Setup(e => e.State).Returns(EntityState.Unchanged);

        var dbContextMock = new Mock<DbContext>();
        dbContextMock.Setup(d => d.Entry(testObject)).Returns(dbEntityEntryMock.Object);

        // Act
        var repository = new CustomerRepository(dbContextMock.Object);
        repository.Delete(testObject);

        //Assert
        dbContextMock.Verify(x => x.Remove(It.Is<Customer>(y => y == testObject)), Times.AtMost(1));
    }

    private static InternalEntityEntry GetInternalEntityEntry(Customer testObject)
    {
        return new InternalEntityEntry(
            new Mock<IStateManager>().Object,
            new RuntimeEntityType(
                name: nameof(Customer),
                type: typeof(Customer),
                sharedClrType: false,
                model: new(),
                baseType: null,
                discriminatorProperty: null,
                changeTrackingStrategy: ChangeTrackingStrategy.Snapshot,
                indexerPropertyInfo: null,
                propertyBag: false,
                discriminatorValue: null),
            testObject);
    }
}