Fix formatting in README (pypa#1642)

Author: hauntsaninja

README.rst

@@ -226,10 +226,10 @@ All images currently contain:
  - `uv <https://pypi.org/p/uv>`_ (not available on ``musllinux s390x`` yet due to Rust limitations)
 
 - All Python interpreters have the following packages pre-installed:
- - `pip <https://pypi.org/p/pip>`_
- - `build <https://pypi.org/p/build>`_
- - `packaging <https://pypi.org/p/packaging>`_
- - Before Python 3.12, `setuptools <https://pypi.org/p/setuptools>`_ and `wheel <https://pypi.org/p/wheel>`_ are also available. (Currently 3.12 too, but will be removed after 3.13 is released.)
+  - `pip <https://pypi.org/p/pip>`_
+  - `build <https://pypi.org/p/build>`_
+  - `packaging <https://pypi.org/p/packaging>`_
+  - Before Python 3.12, `setuptools <https://pypi.org/p/setuptools>`_ and `wheel <https://pypi.org/p/wheel>`_ are also available. (Currently 3.12 too, but will be removed after 3.13 is released.)
 
 - The manylinux-interpreters tool which allows to list all available interpreters & install ones missing from the image