docs: update a broken link

Author: lmxyy

docs/source/usage/kontext.rst

@@ -4,7 +4,7 @@ FLUX.1-Kontext
 .. image:: https://huggingface.co/datasets/nunchaku-tech/cdn/resolve/main/nunchaku/assets/kontext.png
    :alt: FLUX.1-Kontext-dev integration with Nunchaku
 
-Nunchaku supports `FLUX-Kontext-dev <_flux1_kontext_dev>`_,
+Nunchaku supports `FLUX-Kontext-dev <hf_flux-kontext-dev_>`_,
 an advanced model that enables precise image editing through natural language prompts.
 The implementation follows the same pattern as described in :doc:`Basic Usage <./basic_usage>`.