Fix redundant Z-Image terminal timestep (#13730)
* Fix redundant Z-Image terminal timestep
* Update src/diffusers/modular_pipelines/z_image/before_denoise.py
Co-authored-by: dg845 <58458699+dg845@users.noreply.github.com>
* unify sigmas calculation
* update z-image turbo examples
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Co-authored-by: dg845 <58458699+dg845@users.noreply.github.com>
