Link to stable setuptools documentation

Co-authored-by: Andrew Murray <3112309+radarhere@users.noreply.github.com>

Author: nulano

winbuild/build.rst

@@ -97,7 +97,7 @@ To build a wheel instead, run::
     winbuild\build\build_env.cmd
     python.exe -m pip wheel -v -C raqm=vendor -C fribidi=vendor .
 
-.. _editable mode: https://setuptools.pypa.io/en/latest/userguide/development_mode.html
+.. _editable mode: https://setuptools.pypa.io/en/stable/userguide/development_mode.html
 
 Testing Pillow
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