python-pyopenssl: bump to 26.0.0

python-pyopenssl: bump to 26.0.0

Notable changes since 23.3.0:

v26.0.0:
- Drop Python 3.7 support
- Minimum cryptography version is now 46.0.0
- Security fix: properly raise an error if a DTLS cookie callback
  returned a cookie longer than DTLS1_COOKIE_LENGTH bytes, previously
  resulting in a buffer-overflow (CVE-2026-27459)
- Security fix: Context.set_tlsext_servername_callback now handles
  exceptions raised in the callback instead of silently swallowing
  them (CVE-2026-27448)
- Added support for using aws-lc instead of OpenSSL
- Added OpenSSL.SSL.Connection.get_group_name

v25.x:
- Added OpenSSL.SSL.Context.set_tls13_ciphersuites
- Added OpenSSL.SSL.Connection.set_info_callback
- Added OpenSSL.SSL.Context.clear_mode
- pyOpenSSL now sets SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER by default
- typing-extensions added as a runtime dependency (for Python < 3.13)

Full changelog:
https://www.pyopenssl.org/en/stable/changelog.html

Co-Authored-By: Claude Sonnet 4.6 <redacted>
Signed-off-by: Alexandru Ardelean <redacted>