Fix stable diffusion

[divyashreepathihalli]

Fix here - keras-team/keras#19046
Updates to Noise Scheduler
https://arxiv.org/pdf/2305.08891v2.pdf

[sampathweb]

Still failing for Keras 2 GPU.

[dugujiujian1999]

Looks like we have to fix this again for keras-core 0.17

>       self.assertAllEqual(img[0][13:14, 13:14, :][0][0], [66, 38, 185])

args = (<built-in function eq>, array([20,  1, 20], dtype=uint8), array([ 66,  38, 185]))

Maybe the text_to_image gives different value in keras 2 ?