The navigation properties of IQueryable ProjectTo do not require null checks.

[ldqk]

Is your feature request related to a problem? Please describe.
When Project disable nullable reference type,The navigation properties of IQueryable ProjectTo do not require null checks.

Describe the solution you'd like
Source：

[Mapper]
public static partial class PostMapper
{
    [MapProperty("Category.Name", nameof(PostDto.CategoryName))]
    [MapProperty("Comment.Count", nameof(PostDto.CommentsCount))]
    public static partial PostDto ToDto(this Post car);

    public static partial IQueryable<PostDto> Project(this IQueryable<Post> q);
}

public record Category(int Id, string Name);
public record Post(int Id, string Title, string Content, int CategoryId)
{
    public virtual Category Category { get; set; }
    public virtual ICollection<Comment> Comments { get; set; }
}

public record Comment(int Id, string Content, int UserId, int PostId)
{
    public virtual Post Post { get; set; }
}

public record PostDto(int Id, string Title, string Content, int CategoryId)
{
    public string CategoryName { get; set; }
    public int CommentsCount { get; set; }
}

var dtos = dbContext.Posts.Project().ToList();

Actual：

    public static partial class MapperConfigs
    {
        [global::System.CodeDom.Compiler.GeneratedCode("Riok.Mapperly", "4.1.1.0")]
        public static partial global::ConsoleApp1.PostDto? ToDto(this global::ConsoleApp1.Post? car)
        {
            if (car == null)
                return default;
            var target = new global::ConsoleApp1.PostDto(car.Id, car.Title, car.Content, car.CategoryId);
            target.CategoryName = car.Category?.Name;
            if (car.Comments != null)
            {
                target.CommentsCount = car.Comments.Count;
            }
            return target;
        }

        [global::System.CodeDom.Compiler.GeneratedCode("Riok.Mapperly", "4.1.1.0")]
        public static partial global::System.Linq.IQueryable<global::ConsoleApp1.PostDto?>? Project(this global::System.Linq.IQueryable<global::ConsoleApp1.Post?>? q)
        {
            if (q == null)
                return default;
#nullable disable
            return System.Linq.Queryable.Select(
                q,
                x => new global::ConsoleApp1.PostDto(x.Id, x.Title, x.Content, x.CategoryId)
                {
                    CategoryName = x.Category != null && x.Category.Name != null ? x.Category.Name : default,
                    CommentsCount = x.Comments != null ? x.Comments.Count : default,
                }
            );
#nullable enable
        }
    }

The generated SQL:

SELECT p."Title",p."Content", p."CategoryId", p."Id", c."Id", c0."Id", c0."Content", c0."UserId", c0."PostId", (
          SELECT count(*)::int
          FROM "Comment" AS c1
          WHERE p."Id" = c1."PostId"), CASE
          WHEN c."Id" IS NOT NULL AND c."Name" IS NOT NULL THEN c."Name"
      END
      FROM "Post" AS p
      LEFT JOIN "Category" AS c ON p."CategoryId" = c."Id"
      LEFT JOIN "Comment" AS c0 ON p."Id" = c0."PostId"
      ORDER BY p."Id", c."Id"

Expect：

    public static partial class MapperConfigs
    {
        [global::System.CodeDom.Compiler.GeneratedCode("Riok.Mapperly", "4.1.1.0")]
        public static partial global::ConsoleApp1.PostDto? ToDto(this global::ConsoleApp1.Post? car)
        {
            if (car == null)
                return default;
            var target = new global::ConsoleApp1.PostDto(car.Id, car.Title, car.Content, car.CategoryId);
            target.CategoryName = car.Category?.Name;
            if (car.Comments != null)
            {
                target.CommentsCount = car.Comments.Count;
            }
            return target;
        }

        [global::System.CodeDom.Compiler.GeneratedCode("Riok.Mapperly", "4.1.1.0")]
        public static partial global::System.Linq.IQueryable<global::ConsoleApp1.PostDto?>? Project(this global::System.Linq.IQueryable<global::ConsoleApp1.Post?>? q)
        {
            if (q == null)
                return default;
            return System.Linq.Queryable.Select(
                q,
                x => new global::ConsoleApp1.PostDto(x.Id, x.Title, x.Content, x.CategoryId)
                {
                    CategoryName = x.Category.Name,
                    CommentsCount = x.Comments.Count,
                }
            );
        }
    }

Expect generated SQL:

SELECT p."Title", p."Content", p."CategoryId", (
          SELECT count(*)::int
          FROM "Comment" AS c0
          WHERE p."Id" = c0."PostId") AS "CommentCount", c."Name" AS "CategoryName", 
      FROM "Post" AS p
      LEFT JOIN "Category" AS c ON p."CategoryId" = c."Id"