How to unlock the Sqlite database file in EntityFramework.Core

I have a project that uses Microsoft.EntityFrameworkCore.Sqlite 6.0.5 on net6.0. I am expecting the Sqlite database file to be unlocked after the DbContext has been disposed.

However, the behaviour I am observing is that the Sqlite database remains locked after the DbContext has been disposed and finalised. There is a project that reproduces the behaviour here.

How can I unlock the database file?

My DbContext looks like this:

public class MyContext : DbContext
{
    ~MyContext()
    {
        Console.WriteLine("Finaliser was called.");
    }

    public override void Dispose()
    {
        base.Dispose();
        Console.WriteLine("Dispose was called.");
    }

    public static readonly string DbFile = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "_temp.db");

    public DbSet<Foo> Summaries { get; set; }

    protected override void OnModelCreating(ModelBuilder builder)
    {
        builder.Entity<Foo>().HasKey(nameof(Foo.Id));
    }

    protected override void OnConfiguring(DbContextOptionsBuilder options)
    {
        options.UseSqlite($"Data Source={DbFile}");
    }
}

I am using it like this:

public static void AddItem()
{
    using var ctx = new MyContext();
    ctx.Database.EnsureCreated();
    ctx.Summaries.Add(new Foo {Bar = "Foo"});
    ctx.SaveChanges();        
}