Cleanup some older references to Python 2 from python-module(5).

ok?

Index: python-module.5
===================================================================
RCS file: /cvs/src/share/man/man5/python-module.5,v
diff -u -p -u -r1.18 python-module.5
--- python-module.5	16 Aug 2025 16:43:06 -0000	1.18
+++ python-module.5	16 Aug 2025 17:02:58 -0000
@@ -37,12 +37,7 @@ in the
 .Xr ports 7
 tree.
 .Pp
-By default, the module builds ports using Python 3.
-For legacy ports using Python 2,
-.Ev MODPY_VERSION
-may be set manually to ${MODPY_DEFAULT_VERSION_2}.
-.Pp
-The module then sets
+The module sets
 .Ev MODPY_BIN ,
 .Ev MODPY_INCDIR ,
 .Ev MODPY_LIBDIR ,
@@ -135,7 +130,7 @@ Some checks are done to warn during "mak
 .Ev MODPY_PYBUILD
 appears to be set incorrectly.
 .Pp
-Python 2 and some older Python 3 ports using setuptools still set
+Some older ports using setuptools still set
 .Ev MODPY_SETUPTOOLS
 to Yes, which appends to
 .Ev MODPY_BUILD_DEPENDS