[3.13] gh-120831: Increase the default minimum supported iOS version to 13.0 (GH-121250) (#121833)

gh-120831: Increase the default minimum supported iOS version to 13.0 (GH-121250)

Increases the default minimum iOS version to 13.0.

(cherry picked from commit 7e91e0dcfe2faab1e1a4630e6f745aa30ca87b3d)

Co-authored-by: Russell Keith-Magee <russell@keith-magee.com>
Co-authored-by: Erlend E. Aasland <erlend.aasland@protonmail.com>