PEP 518: Do not mention wheel in default [build-system] requires (#4603)

It was never necessary in practice. In the past, setuptools would pull it in through the PEP 517 hook, only when building the wheels. During PyCon 2024, though, wheel moved into the setuptools' codebase and so it's always bundled now, in the modern versions.

Author: hroncok

peps/pep-0518.rst

@@ -164,9 +164,9 @@ the ``pyproject.toml`` file will be::
 
   [build-system]
   # Minimum requirements for the build system to execute.
-  requires = ["setuptools", "wheel"]  # PEP 508 specifications.
+  requires = ["setuptools"]  # PEP 508 specifications.
 
-Because the use of setuptools and wheel are so expansive in the
+Because the use of setuptools is so expansive in the
 community at the moment, build tools are expected to use the example
 configuration file above as their default semantics when a
 ``pyproject.toml`` file is not present.