devel/py-spyder-kernels: Update to 3.0.2

• Improve release instructions for the new backporting workflow
• Add logic to handle traceback color configuration

Changelog: https://github.com/spyder-ide/spyder-kernels/compare/v3.0.1...v3.0.2

Reported by: portscout, Repology
MFH: 2024Q4

(cherry picked from commit cca313f5b496db8da7450689c0f8f676c571b622)