[issue35213] IDLE: use 'macOS' where appropriate.

[Terry J. Reedy]

Terry J. Reedy <tjreedy at udel.edu> added the comment:

This issue is a spinoff of #34864.

----------
nosy: +ned.deily

_______________________________________
Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue35213>
_______________________________________