[3.11] Make use of TESTFN_ASCII in test_fileio (GH-101645) (#101650)

testBytesOpen requires an ASCII filename, but TESTFN usually isn't ASCII.
(cherry picked from commit 6fd5eb640af19b535f4f2ba27b1b61b8d17f02e9)

Co-authored-by: Zachary Ware <zach@python.org>

Miss Islington (bot) committed 3y ago

c38b4e75b1a0532b523351ed974722c0a3b96694

Parent: 7240ba7

Committed by GitHub <noreply@github.com> on 2/8/2023, 10:05:36 AM