devel/py-spyder-kernels: Update to 3.0.3

Bugfix release:

• Correctly process Pdb commands available in cmdqueue
• Use an older Ubuntu version on CIs
• Filter frames that come from Spyder-kernels in tracebacks and fix tracebacks in Python 3.8

Changelog: https://github.com/spyder-ide/spyder-kernels/compare/v3.0.2...v3.0.3

Reported by: portscout, Repology
MFH: 2025Q1