[3.12] gh-102988: Detect email address parsing errors and return empty tuple to indic...

[3.12] gh-102988: Detect email address parsing errors and return empty tuple to indicate the parsing error (old API) (GH-105127) (#106612)

gh-102988: Detect email address parsing errors and return empty tuple to indicate the parsing error (old API) (GH-105127)

Detect email address parsing errors and return empty tuple to indicate the parsing error (old API). This fixes or at least ameliorates CVE-2023-27043.

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(cherry picked from commit 18dfbd035775c15533d13a98e56b1d2bf5c65f00)

Co-authored-by: Thomas Dwyer <github@tomd.tel>
Co-authored-by: Gregory P. Smith <greg@krypto.org>