Keras Fix the Doc of alpha in mobilenet_v3

Doc Issue

The doc of mobilenet_v3 shows its description as below:

https://github.com/keras-team/keras/blob/4e1b250491627f871f6c82c0dcb577cc21093def/keras/src/applications/mobilenet_v3.py#L91-L99

Which version I tried in is of TensorFlow 2.19.0:

For the repro below, I accept that it should raise error, but should be noted in docs that arg alpha only has choices in [0.75, 1.0] when weights is of default value "imagenet".

Repro

import tensorflow as tf
import numpy as np

file_name = 'file.npy'
np.save(file_name, (np.random.rand(160, 160, 3) * 255.0))
model = tf.keras.applications.MobileNetV3Small(input_shape=(160, 160, 3), alpha=0.5, include_top=False)
model.compile(optimizer='adam', loss='categorical_crossentropy', metrics=['accuracy'])
print(model.summary())

Output

ValueError: If imagenet weights are being loaded, alpha can be one of `0.75`, `1.0` for non minimalistic or `1.0` for minimalistic only.

Raise Codes are here:

https://github.com/keras-team/keras/blob/4e1b250491627f871f6c82c0dcb577cc21093def/keras/src/applications/mobilenet_v3.py#L268-L279

Thanks a lot!