python-pymysql: update to 1.1.3

python-pymysql: update to 1.1.3

Security fix:
- Fix Cursor.callproc() to escape procedure name, preventing SQL injection
  when calling a procedure with a string received from an untrusted source
- NOTICE: Backward compatibility change - procedure names like
  "dbname.funcname" are now backtick-quoted: ``CALL \`dbname.funcname\` ``

Other changes:
- CI: use ubuntu-slim, add dependabot for GitHub Actions
- Bump GitHub Actions (checkout v4→v6, setup-python v5→v6, codecov v5→v6)
- Add publish.yml workflow (copied from psf/requests)
- Upgrade dependencies: cryptography>=46.0.7, PyNaCl>=1.6.2
- Drop Python 3.8, require Python 3.9+

Changelog:
https://github.com/PyMySQL/PyMySQL/releases/tag/v1.1.3

NOTE: added test.sh for basic validation.

Signed-off-by: Alexandru Ardelean <redacted>