Remove redundant wheel dep from pyproject.toml

Remove the redundant `wheel` dependency, as it is added by the backend
automatically.  Listing it explicitly in the documentation was
a historical mistake and has been fixed since, see:
pypa/setuptools@f7d30a9

Author: mgorny

pyproject.toml

@@ -1,6 +1,6 @@
 [build-system]
 # Minimum requirements for the build system to execute.
-requires = ["setuptools>=61.2", "wheel"]
+requires = ["setuptools>=61.2"]
 build-backend = "setuptools.build_meta"
 
 [project]