bpo-32262: Fix typo in f-string (GH-7016)

Fix typo from commit 6370f345e1d5829e1fba59cd695c8b82c5a8c620

Signed-off-by: Christian Heimes <christian@python.org>

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<!-- issue-number: bpo-32262 -->
https://bugs.python.org/issue32262
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