python wheel test norms

[Greg Troxel <gdt%lexort.com@localhost>]

In net/py-magic-wormhole, upstream documents tox for tests but does not
mention py-test.

wheel.mk has USE_PYTEST defaulting to yes, which TEST_DEPENDS on py-test
and creates a do-test target to run it.

Is it such a strong convention in python that of course py-test is needed and
is the standard entry point to run tests, that it's not a bug for an
upstream to omit mentioning it?

Exactly one package has USE_PYTEST=no (because there are no tests).

Or, is it otherwise?

--- wheel.mk.~1.20.~	2025-02-02 10:26:12.000000000 -0500
+++ wheel.mk	2025-04-08 12:22:15.835086548 -0400
@@ -24,6 +24,8 @@
 #			Only needs to be set if do-build is redefined.
 #
 # USE_PYTEST:		If set to yes, depend on py-test and use it for testing.
+#			(This is strongly the standard approach, to
+#			the point that upstreams will not document it.)
 #			Default: yes
 #
 # WHEEL_ARGS:		Additional arguments to pass during build of the wheel.