[docs] fix references in flux pipelines. (#11857)
* fix references in flux.
* Update src/diffusers/pipelines/flux/pipeline_flux_kontext.py
Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>
---------
Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>
