BLD Make the version dynamic in pyproject.toml (scikit-learn#29399)

Co-authored-by: Loïc Estève <loic.esteve@ymail.com>

Author: jeromedockes

doc/developers/maintainer.rst

@@ -105,12 +105,12 @@ This PR will be used to push commits related to the release as explained in
 :ref:`making_a_release`.
 
 You can also create a second PR from main and targeting main to increment the
-``__version__`` variable in `sklearn/__init__.py` and in `pyproject.toml` to increment
-the dev version. This means while we're in the release candidate period, the latest
-stable is two versions behind the main branch, instead of one. In this PR targeting
-main you should also include a new file for the matching version under the
-``doc/whats_new/`` folder so PRs that target the next version can contribute their
-changelog entries to this file in parallel to the release process.
+``__version__`` variable in `sklearn/__init__.py` to increment the dev version.
+This means while we're in the release candidate period, the latest stable is
+two versions behind the main branch, instead of one. In this PR targeting main
+you should also include a new file for the matching version under the
+``doc/whats_new/`` folder so PRs that target the next version can contribute
+their changelog entries to this file in parallel to the release process.
 
 Minor version release (also known as bug-fix release)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -211,7 +211,7 @@ Making a release
      enough) and to update the on-going development entry.
 
 2. On the branch for releasing, update the version number in ``sklearn/__init__.py``,
-   the ``__version__`` variable, and in `pyproject.toml`.
+   the ``__version__`` variable.
 
    For major releases, please add a 0 at the end: `0.99.0` instead of `0.99`.
 

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "scikit-learn"
-version = "1.6.dev0"
+dynamic = ["version"]
 description = "A set of python modules for machine learning and data mining"
 readme = "README.rst"
 maintainers = [