WC-1931:lf_interop_ping_plotter.py: Fix ping test if generic tab check is not present - #361

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: py-actions/flake8@v2. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/