`Lazy=True` ignored when using `Dataset` call

[KumoLiu]

Describe the bug
Dataset call, lazy=True ignored

To Reproduce

import monai.transforms as mt
from monai.data import Dataset

d = {"image": "tests/testing_data/ref_avg152T1_LR.nii.gz"}
xform = mt.Compose(
    [
        mt.LoadImaged(keys="image"),
        mt.RandAffined(keys="image", prob=1.0, rotate_range=45.0, translate_range=10.0, scale_range=0.15),
    ],
    lazy=True,
    log_stats=True,
)
out_1 = xform(d)  # direct call works fine

x = Dataset([d], transform=xform)  # dataset call, lazy=True ignored
out_2 = x[0]