phx.gen.cert cannot generate a certificate on 2024-02-29 with a valid end date

[quitejonny]

Environment

• Elixir version: 1.15.7
• Phoenix version (mix deps): 1.7.10
• Operating system: Ubuntu 22.04

Actual behavior

The task phx.gen.cert could not generate a certificate on 2024-02-29 with a valid end date.
It would try to use 2025-02-29 as the end date.
Today (2024-02-29) the phoenix tests (test/mix/tasks/phx.gen.cert_test.exs) are failing.

Expected behavior

You can generate a certificate with valid end date on 2028-02-29.

I provided a fix #5736

[chrismccord]

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