Fix artifacts when CXR samples values are outside 0, 1 range

[Warvito]

Before multiplying the values of the samples to 255 and cast it to int8, it is necessary clip the values to avoid out of range artifacts.

GenerativeModels/model-zoo/models/cxr_image_synthesis_latent_diffusion_model/scripts/saver.py

Line 15 in 24b0039

image_data = (image_data * 255).astype(np.uint8)