python3: update to 3.8.18

python3: update to 3.8.18

https://docs.python.org/release/3.8.18/whatsnew/changelog.html#changelog

Release date: 2023-08-24

Security
gh-108310: Fixed an issue where instances of ssl.SSLSocket were
vulnerable to a bypass of the TLS handshake and included protections
(like certificate verification) and treating sent unencrypted data as if
it were post-handshake TLS encrypted data. Security issue reported as
CVE-2023-40217 by Aapo Oksman. Patch by Gregory P. Smith.

Library
gh-107845: tarfile.data_filter() now takes the location of symlinks into
account when determining their target, so it will no longer reject some
valid tarballs with LinkOutsideDestinationError.

Tools/Demos
gh-107565: Update multissltests and GitHub CI workflows to use OpenSSL
1.1.1v, 3.0.10, and 3.1.2.

Signed-off-by: Lee Chee Yang <chee.yang.lee@intel.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>