When generating certificates with
`Crypto.generate_self_signed_certificate` we generate the PEM in a
buffer via `mbedtls_x509write_crt_pem`.
Since version 2.16.8, mbedtls adds spurious data at the end of the
buffer due to internal optimizations, this breaks our logic when we try
to immediately parse it and return a proper `X509Certificate` object.
This commit updates the code to find the actual PEM length to parse
using `strlen`, takes extra caution always adding the terminator to the
buffer, and slightly improve error messages.
(cherry picked from commit 60687ce778)
Happy new year to the wonderful Godot community!
We're starting a new decade with a well-established, non-profit, free
and open source game engine, and tons of further improvements in the
pipeline from hundreds of contributors.
Godot will keep getting better, and we're looking forward to all the
games that the community will keep developing and releasing with it.
